Repair of uninterruptible power supplies (UPS repair). Do-it-yourself UPS repair: wizard's advice Repair of apc uninterruptible power supplies

The Elemont + company carries out repair of uninterruptible power supplies power supply (UPS repair) UPS in Moscow and the nearest cities of the Moscow region - Mytishchi, Korolev, Pushkino, Dolgoprudny. We work with both individuals and legal entities. It is possible to conclude a service contract and repair, how uninterruptible power supplies and office equipment in general. Payment can be made by bank transfer.

Repair of uninterruptible power supplies (UPS) in Elemont +

Working at a computer for a long time, developing a new program or just typing a text, a person does not always think that due to problems with the power supply, his many hours of work can go down the drain. A slight drop in voltage or a sudden power outage will not allow time for the results to be saved. For these purposes, uninterruptible power supplies (UPS) are used, which are able to keep the computer running for some time without electricity. This time is enough to save the necessary files to the hard disk of the computer or to a removable storage device and to shut down the operating system correctly.

Repair of uninterruptible power supplies (UPS repair). General price list

P / p No.	Equipment type	Diagnostics and repair, rub.
1	Uninterruptible power supplies UPS up to 6 kVA	from 800
2	Uninterruptible power supplies UPS from 6 kVa to 15 kVa	from 4400
3	Uninterruptible power supplies UPS from 20 kVa to 40 kVa	from 5800
4	Uninterruptible power supplies UPS from 120 kVa and above	from 6900
5	Replacing UPS batteries	from 300
6	Mains voltage regulator (depends on power)	from 800

Our company also carries out routine maintenance work on uninterruptible power supplies and voltage stabilizers. To estimate the cost of services, send your proposal to the mail This email address is being protected from spambots. You need JavaScript enabled to view it.

Typical UPS faults

The main problem with almost all budget models of uninterruptible power supplies is the battery. The lion's share of low-price UPS comes without a voltage stabilization unit. In such models, protection against small voltage surges is carried out by a short-term switch to battery operation.

If in your network the phenomenon of voltage drops is quite frequent, then replacement battery of such UPS will be needed very soon. However, if such problems are not observed, then it is inappropriate to spend money on the purchase of a more expensive UPS.

An uninterruptible power supply is a rather complex device, which can be conditionally divided into two units - a 12V-to-220V network converter, and a charger that performs the opposite function: 220V to 12V to recharge the battery. In most cases, repairing an uninterruptible power supply is very problematic and expensive. But it's still worth trying - of course there is always a chance for a freebie in the form of a blown fuse :)

A friend at the company threw out a non-working uninterruptible power supply of the APC 500 model. But before putting it into spare parts, I decided to try to revive it. And as it turned out, it was not in vain. First of all, we measure the voltage on the rechargeable gel battery. For the operation of the uninterruptible power supply, but must be within 10-14V. The voltage is normal, so there is no problem with the battery.

Now let's examine the board itself and measure the power supply at key points in the circuit. I did not find a native circuit diagram of the APC500 uninterruptible power supply, but here's something similar. For better clarity, download the full one here. We check powerful tin transistors - the norm. The power supply to the electronic control part of the uninterruptible power supply comes from a small 15V mains transformer. We measure this voltage before the diode bridge, after, and after the 9V stabilizer.

And here is the first swallow. The 16V voltage after the filter enters the microcircuit - the stabilizer, and the output is only a couple of volts. We replace it with a model similar in voltage and restore the power supply to the control unit circuit.

The uninterruptible power supply began to crack and buzz, but it is still not observed at the output of 220V. We continue to carefully examine the printed circuit board.

Another problem - one of the thin tracks burned out and had to be replaced with a thin wire. Now the APC500 uninterruptible power supply unit worked without problems.

Testing in real conditions, I came to the conclusion that the built-in squeaker, the no-network signaling device, screams like a bad one, and it would not hurt to calm it down a little. It is impossible to turn off completely - since the state of the battery in emergency mode will not be heard (determined by the frequency of signals), but it is possible and necessary to make it quieter.

This is achieved by connecting a 500-800 ohm resistor in series with the sounder. And finally, a few tips for owners of uninterruptible power supplies. If he disconnects the load occasionally, there may be a problem with the "dried out" capacitors. Connect the UPS to the input of a known good computer and see if the operation stops.

An uninterruptible power supply sometimes incorrectly determines the capacity of lead-acid batteries, showing the OK status, but as soon as it switches to them, they suddenly sit down and the load is "knocked out". Make sure the terminals fit snugly and not loose. Do not disconnect it from the network for a long time, making it impossible to keep the batteries on a constant recharge. Do not allow deep discharges of the batteries, leaving at least 10% of the capacity, after which the UPS should be turned off until the supply voltage is restored. At least once every three months, do a "workout" by discharging the battery to 10% and recharging the battery to full capacity.

Discuss the article UNINTERRUPTOR REPAIR

The complete lack of information about such common devices as uninterruptible power supplies is surprising. We are breaking through the information blockade and are starting to publish materials on their construction and repair. From the article you will get a general idea of ​​the existing types of uninterruptible power supplies and a more detailed, at the level of a schematic diagram, about the most common Smart-UPS models.

The reliability of computers is largely determined by the quality of the electrical network. Power interruptions, such as surges, surges, sags, and power outages, can result in keyboard locks, data loss, system board damage, and more. Uninterruptible power supplies (UPS) are used to protect high-value computers from mains-related troubles. The UPS eliminates problems associated with poor quality power or temporary lack of power, but is not a long-term alternative power source like a generator.

According to the expert-analytical center "SK PRESS", in 2000 the volume of UPS sales in the Russian market amounted to 582 thousand units. If we compare these estimates with data on sales of computers (1.78 million pieces), it turns out that in 2000, every third computer purchased is equipped with an individual UPS.

The overwhelming part of the Russian UPS market is occupied by products of six companies: APC, Chloride, Invensys, IMV, Liebert, Powercom. APC products have been maintaining the leading position in the Russian UPS market for many years now.

UPSs are divided into three main classes: Off-line (or stand-by), Line-interactive and On-line. These devices have various designs and characteristics.

Rice. 1. Block diagram of an off-line UPS

A block diagram of an Off-line UPS is shown in Fig. 1. During normal operation, the load is supplied by the filtered mains voltage. EMI / RFI Noise filters on metal oxide varistors are used to suppress EMI and RFI in the input circuits. If the input voltage falls below or above the set value, or disappears altogether, the inverter turns on, which is normally off. By converting the DC voltage of the batteries into AC, the inverter supplies the load from the batteries. The shape of its output voltage is rectangular pulses of positive and negative polarity with an amplitude of 300 V and a frequency of 50 Hz. Off-line UPSs operate uneconomically in power grids with frequent and significant voltage deviations from the nominal value, since frequent switching to battery operation reduces the service life of the latter. The power of the Off-line UPS models manufactured by ARS, the Back-UPS model, is in the range of 250 ... 1250 VA, and for the Back-UPS Pro models, in the range of 2S0 ... 1400 VA.

Rice. 2. Block diagram of a Line-interactive UPS

A block diagram of a Line-interactive UPS is shown in Fig. 2. Just like the Off-line UPS, they relay the AC mains voltage to the load, while absorbing relatively small voltage surges and smoothing out noise. The input circuits use an EMI / RFI Noise filter on metal oxide varistors to suppress EMI and RFI. If an emergency occurs in the power grid, then the UPS synchronously, without loss of the oscillation phase, turns on the inverter to supply the load from the batteries, while the sinusoidal shape of the output voltage is achieved by filtering the PWM oscillation. The circuit uses a special inverter to recharge the battery, which also works during line voltage surges. The range of operation without battery connection is expanded due to the use of an autotransformer with a switched winding in the input circuits of the UPS. Transition to battery power occurs when utility voltage is out of range. The power of the Line-interactive class Smart-UPS UPS manufactured by ARS is 250 ... 5000 VA.

Rice. 3. Block diagram of the UPS class On-line

The block diagram of the UPS of the On-line class is shown in Fig. 3. These UPSs convert the AC input voltage to DC, which is then converted back to stable AC by means of a PWM inverter. Since the load is always supplied by the inverter, there is no need to switch from the mains to the inverter, and the transfer time is zero. Due to the inertial DC link, which is the battery, the load is isolated from mains anomalies and a very stable output voltage is formed. Even with large deviations in the input voltage, the UPS continues to supply the load with pure sinusoidal voltage with a deviation of no more than + 5% of the user-set nominal value. APC On-line UPSs have the following output powers: Matrix UPS models - 3000 and 5000 VA, Symmetra Power Array models - 8000, 12000 and 16000 VA.

The Back-UPS models do not use a microprocessor, while the Back-UPS Pro, Smart-UPS, Smart / VS, Matrix, and Symmetna use a microprocessor.

The most widely used devices are: Back-UPS, Back-UPS pro, Smart-UPS, Smart-UPS / VS.

Devices such as Matrix and Symmetna are used primarily for banking systems.

In this article, we will consider the design and diagram of Smart-UPS 450VA ... 700VA models used to power personal computers (PCs) and servers. Their technical characteristics are given in table. 1.

Table 1. Specifications for APC Smart-UPS models

Model	450VA	620VA	700VA	1400VA
Allowable input voltage, V	0...320
Input voltage for mains operation *, V	165...283
Output voltage *, V	208...253
Input circuit overload protection	Resettable circuit breaker
Frequency range for mains operation, Hz	47...63
Time of switching to battery power, ms	4
Maximum load power, VA (W)	450(280)	620(390)	700(450)	1400(950)
Output voltage during battery operation, V	230
Frequency when operating on battery, Hz	50 ± 0.1
Signal waveform when operating on battery power	Sinusoid
Output circuit overload protection	Overload and short-circuit protection, overload latching shutdown
Battery Type	Lead sealed, maintenance-free
Number of batteries x voltage, V,	2 x 12	2 x 6	2 x 12	2 x 12
Battery capacity, Ah	4,5	10	7	17
Battery life, years	3...5
Full charge time, h	2...5
UPS dimensions (height x width x length), cm	16.8x11.9x36.8		15,8x13,7x35,8	21.6x17x43.9
Net weight (gross), kg	7,30(9,12)	10,53(12,34)	13,1(14,5)	24,1(26,1)

* User adjustable using PowerChute software.

UPS Smart-UPS 450VA ... 700VA and Smart-UPS 1000VA ... 1400VA have the same electrical circuit and differ in battery capacity, the number of output transistors in the inverter, the power of the power transformer and dimensions.

Consider the parameters that characterize the quality of electricity, as well as terminology and designations.

Power problems can be expressed as:

complete absence of input voltage - blackout;

temporary absence or strong voltage drop caused by the inclusion of a powerful load (electric motor, elevator, etc.) into the network - sag or brownout;

instant and very powerful increase in voltage, as in a lightning strike - spike;

periodic increase in voltage, lasting a fraction of a second, caused, as a rule, by changes in the load in the network - surge.

In Russia, voltage dips, power outages and surges both up and down account for approximately 95% of deviations from the norm, the rest is noise, impulse noise (needles), high-frequency surges.

Volt-Amperes (VA, VA) and Watts (W, W) are used as power units. They differ in power factor PF (Power Factor):

The power factor for computer technology is 0.6 ... 0.7. The number in the designation of APC UPS models indicates the maximum power in VA. For example, the Smart-UPS 600VA model has a power of 400W, and the 900VA model has 630W.

The block diagram of the Smart-UPS and Smart-UPS / VS models is shown in Fig. 4. Mains voltage is applied to the EM / RFI input filter to suppress mains noise. At rated mains voltage, relays RY5, RY4, RY3 (pins 1, 3), RY2 (pins 1, 3), RY1 are switched on, and the input voltage is passed to the load. Relays RY3 and RY2 are used for the BOOST / TRIM output voltage trim mode. For example, if the mains voltage increased and went beyond the permissible limit, relays RY3 and RY2 connect an additional winding W1 in series with the main W2. An autotransformer with a transformation ratio is formed

K = W2 / (W2 + W1)

less than one and the output voltage drops. In the event of a decrease in the mains voltage, the additional winding W1 is reversed by the relay contacts RY3 and RY2. Transformation ratio

K = W2 / (W2 - W1)

becomes greater than one, and the output voltage rises. The adjustment range is ± 12%, the hysteresis value is selected by the Power Chute software.

In the event of a voltage loss at the input, the RY2 ... RY5 relays are turned off, a powerful PWM inverter powered by a battery turns on, and a sinusoidal voltage of 230 V, 50 Hz is supplied to the load.

The multi-tier power grid noise suppression filter consists of varistors MV1, MV3, MV4, choke L1, capacitors C14 ... C16 (Fig. 5). The CT1 transformer analyzes the high-frequency components of the mains voltage. The CT2 transformer is a load current sensor. The signals from these sensors, as well as the RTH1 temperature sensor, are fed to the analog-to-digital converter IC10 (ADC0838) (Fig. 6).

Transformer T1 is an input voltage sensor. The command to turn on the device (AC-OK) is sent from the two-level comparator IC7 to the base of Q6. Transformer T2 - output voltage sensor for Smart TRIM / BOOST mode. From pins 23 and 24 of IC1 2 (Fig. 6), the BOOST and TRIM signals are fed to the bases of transistors Q43 and Q49 to switch relays RY3 and RY2, respectively.

The phase synchronization signal (PHAS-REF) from pin 5 of transformer T1 goes to the base of transistor Q41 and from its collector to pin 14 of IC12 (Figure 6).

The Smart-UPS model uses an IC12 microprocessor (S87C654), which:

monitors the presence of voltage in the mains. If it disappears, then the microprocessor connects a powerful inverter powered by a battery;

turns on a beep to notify the user of power problems;

provides safe automatic shutdown of the operating system (Netware, Windows NT, OS / 2, Scounix and Unix Ware, Windows 95/98), saving data through a bi-directional switching port with the installed Power Chute plus software;

automatically corrects for drops (Smart Boost mode) and overshoots (Smart Trim mode) of the mains voltage, bringing the output voltage to a safe level without switching to battery operation;

monitors the battery charge, tests it with a real load and protects it from overcharging, ensuring continuous charging;

provides battery replacement mode without power off;

conducts a self-test (every two weeks or by pressing the Power button) and issues a warning about the need to replace the battery;

indicates the level of battery recharge, mains voltage, UPS load (the number of equipment connected to the UPS), battery power mode and the need to replace it.

The EEPROM IC13 contains the factory settings, as well as the calibrated settings for the signal levels of frequency, output voltage, transition limits, battery charging voltage.

Digital-to-analog converter IC15 (DAC-08CN) generates a sinusoidal reference signal at pin 2, which is used as a reference for IC17 (APC2010).

The PWM signal is generated by IC14 (APC2020) in conjunction with IC17. Powerful field-effect transistors Q9 ... Q14, Q19 ... Q24 form a bridge inverter. During the positive half-wave of the PWM signal, Q12 ... Q14 and Q22 ... Q24 are open, and Q19 ... Q21 and Q9 ... Q11 are closed. During the negative half-wave, Q19 ... Q21 and Q9 ... Q11 are open, and Q12 ... Q14 and Q22 ... Q24 are closed. Transistors Q27 ... Q30, Q32, Q33, Q35, Q36 form push-pull drivers that generate control signals for powerful field-effect transistors with a large input capacitance. The load of the inverter is the transformer winding, it is connected by wires W5 (yellow) and W6 (black). A sinusoidal voltage of 230 V, 50 Hz is generated on the secondary winding of the transformer to power the connected equipment.

Inverter reverse operation is used to charge the battery with a ripple current during normal UPS operation.

The UPS has a built-in SNMP slot that allows you to connect additional cards to expand the UPS's capabilities:

Power Net SNMP adapter that supports direct connection to the server in case of emergency shutdown of the system;

UPS interface extender to manage up to three servers;

a Call-UPS remote control device that provides remote access via a modem.

The UPS has several voltages required for the normal operation of the device: 24 V, 12 V, 5 V and -8 V. To check them, you can use table. 2. Measure the resistance from the terminals of the microcircuits to the common wire with the UPS turned off and the discharged capacitor C22. Typical malfunctions of UPS Smart-Ups 450VA ... 700VA and methods of their elimination are shown in table. 3.

Table 3. Typical UPS faults Smart-Ups 450VA ... 700VA

Brief description of the defect	Possible reason	Troubleshooting method
UPS does not turn on	Batteries not connected	Connect batteries
	Bad or defective battery, low capacity	Replace battery. The capacity of the charged battery can be checked with the high beam lamp from the car (12V, 150W)
	Powerful field-effect transistors of the inverter are pierced	In this case, there is no voltage at the terminals of the battery connected to the UPS board. Check with an ohmmeter and replace transistors. Check the resistors in their gate circuits. Replace IC16
	Broken flexible cable connecting the display	This fault can be caused by shorting the flex cable leads in the UPS chassis. Replace the flex cable that connects the display to the main board of the UPS. Check if fuse F3 and transistor Q5 are working
	The power button is pressed	Replace SW2 button
The UPS powers up on battery power only	Fuse F3 blown	Replace F3. Check the health of transistors Q5 and Q6
UPS will not start. Battery replacement indicator is on	If the battery is good, the UPS is not running the program correctly.	Calibrate the battery voltage using the proprietary program from APC
UPS does not come on line	Mains cable cut or connection broken	Connect the network cable. Check the condition of the automatic plug with an ohmmeter. Check the hot-neutral cord connection.
	Cold soldering of board elements	Check the health and quality of the rations of elements L1, L2 and especially T1
	Defective varistors	Check or replace varistors MV1 ... MV4
Load shedding occurs when the UPS is turned on.	Defective voltage sensor T1	Replace T1. Check the health of the elements: D18 ... D20, C63 and C10
Display indicators are flashing	The capacity of the capacitor C17 has decreased	Replace capacitor C17
	Capacitor leakage is likely	Replace C44 or C52
	Defective relay contacts or board elements	Replace relay. Replace IC3 and D20. D20 diode is better to replace with 1N4937
UPS overload	The connected equipment exceeds the rated power	Reduce load
	Defective transformer T2	Replace T2
	Defective current sensor CT1	Replace CT1. A resistance greater than 4 ohms indicates a faulty current sensor
	Defective IC15	Replace IC15. Check the voltage -8 V and 5 V. Check and replace if necessary: ​​IC12, IC8, IC17, IC14 and the power field-effect transistors of the inverter. Check power transformer windings
Battery does not charge	UPS program is not working properly	Calibrate the battery voltage with a proprietary program from the APC. Check constants 4, 5, 6, 0. Constant 0 is critical for every UPS model. Check the constant after replacing the battery
	The battery charging circuit is out of order	Replace IC14. Check the 8 V voltage at the pin. 9 IC14, if not, replace C88 or IC17
	Battery defective	Replace battery. Its capacity can be checked with a high beam lamp from a car (12V, 150W)
	Microprocessor IC12 defective	Replace IC12
UPS does not start when turned on, click is heard	Defective reset circuit	Check serviceability and replace faulty elements: IC11, IC15, Q51 ... Q53, R115, C77
Indicator defect	The indication circuit is faulty	Check and replace faulty Q57 ... Q60 on the indicator board
UPS does not work in On-line mode	Defective board elements	Replace Q56. Check the health of the elements: Q55, Q54, IC12. IC13 is defective or will have to be reprogrammed. The program can be taken from a working UPS
When transferring to battery operation, the UPS shuts down and turns on spontaneously	Broken transistor Q3	Replace transistor Q3

In the second part of the article, the UPS device of the On-line class will be considered,

OFF-LINE UPS UNIT

APC Off-line UPS includes Back-UPS models. UPSs of this class are distinguished by their low cost and are designed to protect personal computers, workstations, network equipment, trade and point-of-sale terminals. The power of the manufactured Back-UPS models is from 250 to 1250 VA. The main technical data of the most common UPS models are presented in table. 3.

Table 3. Main technical data of UPS class Back-UPS

Model	BK250I	BK400I	BK600I
Rated input voltage, V	220...240
Rated mains frequency, Hz	50
Energy of absorbed emissions, J	320
Peak emission current, A	6500
IEEE 587 Cat. A 6kVA,%	<1
Switching voltage, V	166...196
Output voltage when operating from batteries, V	225 ± 5%
Output frequency when operating on batteries, Hz	50 ± 3%
Maximum power, VA (W)	250(170)	400(250)	600(400)
Power factor	0,5. ..1,0
Crest factor	<5
Nominal switching time, ms	5
Number of batteries x voltage, V	2x6	1x12	2x6
Battery capacity, Ah	4	7	10
Time of 90% recharging after discharging to 50%, hour	6	7	10
Acoustic noise at a distance of 91 cm from the device, dB	<40
UPS operating time at full capacity, min	>5
Maximum dimensions (H x W x D), mm	168x119x361
Weight, kg	5,4	9,5	11,3

The index "I" (International) in the names of UPS models means that the models are designed for an input voltage of 230 V, the devices are equipped with sealed lead-acid maintenance-free batteries with a service life of 3 ... 5 years according to the Euro Bat standard. All models are equipped with suppressor filters that suppress surges and high-frequency noise in the mains voltage. The devices give appropriate audible signals when the input voltage is lost, the batteries are discharged and overloaded. The utility voltage threshold below which the UPS switches to battery operation is set using the switches on the rear of the unit. Models BK400I and BK600I have an interface port connected to a computer or server for automatic self-closing of the system, a test switch and an audible signal switch.

The block diagram of the UPS Back-UPS 250I, 400I and 600I is shown in Fig. 8. Mains voltage is supplied to the input multistage filter through a circuit breaker. The circuit breaker is designed as a circuit breaker on the back of the UPS. In the event of a significant overload, it disconnects the device from the mains, while the contact column of the switch is pushed up. To turn on the UPS after an overload, it is necessary to reset the contact bar of the breaker. The input EMI and RFI filter uses LC links and metal oxide varistors. During normal operation, pins 3 and 5 of RY1 are closed and the UPS transfers utility power to the load, filtering out high frequency interference. The charging current flows continuously as long as there is voltage in the network. If the input voltage drops below the set value or disappears altogether, or if it is very noisy, contacts 3 and 4 of the relay close, and the UPS switches to operation from the inverter, which converts the DC voltage of the batteries into AC. The switching time is about 5 ms, which is quite acceptable for modern switching power supplies for computers. The waveform at the load is rectangular pulses of positive and negative polarity with a frequency of 50 Hz, a duration of 5 ms, an amplitude of 300 V, an effective voltage of 225 V. At idle, the pulse duration is reduced, and the effective output voltage drops to 208 V. Unlike Smart models -UPS, the Back-UPS does not have a microprocessor, comparators and logic chips are used to control the device.

A schematic diagram of the Back-UPS 250I, 400I and 600I is almost completely shown in Fig. 9 ... 11. The multi-tier power supply noise suppression filter consists of varistors MOV2, MOV5, chokes L1 and L2, capacitors C38 and C40 (Fig. 9). Transformer T1 (Fig. 10) is an input voltage sensor. Its output voltage is used for battery charging (this circuit uses D4 ... D8, IC1, R9 ... R11, C3 and VR1) and for analyzing the mains voltage.

If it disappears, then the circuit on the elements IC2 ... IC4 and IC7 connects a powerful inverter powered by a battery. The ACFAIL command to turn on the inverter is generated by IC3 and IC4. The circuit, consisting of comparator IC4 (pins 6, 7, 1) and electronic key IC6 (pins 10, 11, 12), enables the operation of the inverter with a log signal. "1" on pins 1 and 13 of IC2.

The divider consisting of resistors R55, R122, R1 23 and switch SW1 (pins 2, 7 and 3, 6) located on the rear side of the UPS determines the mains voltage below which the UPS switches to battery power. The factory setting for this voltage is 196 V. In areas with frequent fluctuations in the mains voltage resulting in frequent UPS switches to battery power, the threshold voltage should be set to a lower level. The fine adjustment of the threshold voltage is performed by the VR2 resistor.

During battery operation, IC7 generates inverter excitation pulses PUSHPL1 and PUSHPL2. In one arm of the inverter, powerful field-effect transistors Q4 ... Q6 and Q36 are installed, in the other -Q1 ... Q3 and Q37. The transistors are loaded by their collectors on the output transformer. The secondary winding of the output transformer generates an impulse voltage with an effective value of 225 V and a frequency of 50 Hz, which is used to power the equipment connected to the UPS. The duration of the pulses is regulated by the variable resistor VR3, and the frequency - by the resistor VR4 (Fig. 10). Turning on and off the inverter is synchronized with the mains voltage by the circuit on the elements IC3 (pins 3 ... 6), IC6 (pins 3 ... 5, 6, 8, 9) and IC5 (pins 1 ... 3 and 11 ... 13). Circuit on the elements SW1 (pins 1 and 8), IC5 (pins 4 ... B and 8 ... 10), IC2 (pins 8 ... 10), IC3 (pins 1 and 2), IC10 (pins 12 and 13), D30, D31, D18, Q9, BZ1 (fig. 11) activates the buzzer to warn the user of power supply problems. During battery operation, the UPS emits a single beep every 5 seconds to indicate the need to save user files. battery capacity is limited. When operating on battery power, the UPS monitors battery capacity and emits a continuous beep before battery discharge. If pins 4 and 5 of switch SW1 are open, then this time is 2 minutes, if closed - 5 minutes. To turn off the sound signal, close the terminals 1 and 8 of the SW1 switch.

All Back-UPS models, with the exception of the BK250I, have a bi-directional communication port for communication with a PC. Power Chute Plus software allows the computer to perform both UPS monitoring and safe automatic shutdown of the operating system (Novell, Netware, Windows NT, IBM OS / 2, Lan Server, Scounix and UnixWare, Windows 95/98) while saving user files. In fig. 11 this port is designated J14. Purpose of its conclusions: 1 - UPS SHUTDOWN. The UPS shuts down if a log appears on this pin. "1" for 0.5 s.
2 - AC FAIL. When switching to battery power, the UPS generates a log on this pin. "1".
3 - CC AC FAIL. When switching to battery power, the UPS generates a log on this output. "0". Open collector output.
4, 9 - DB-9 GROUND. Common wire for signal input / output. The terminal has a resistance of 20 ohms with respect to the common wire of the UPS.
5 - CC LOW BATTERY. In case of battery discharge, the UPS generates a log on this output. "0". Open collector output.
6 - OS AC FAIL When switching to battery power, the UPS generates a log on this output. "1". Open collector output.
7, 8 - not connected.

Open collector outputs can be connected to TTL circuits. Their load capacity is up to 50 mA, 40 V. If you need to connect a relay to them, then the winding should be shunted with a diode.

A regular "null modem" cable is not suitable for this port, the corresponding RS-232 interface cable with a 9-pin connector is supplied with the software.

UPS CALIBRATION AND REPAIR

Setting the frequency of the output voltage

To set the frequency of the output voltage, connect an oscilloscope or frequency meter to the UPS output. Turn the UPS into battery mode. When measuring the frequency at the UPS output, adjust the VR4 resistor to 50 ± 0.6 Hz.

Setting the output voltage value

Turn the UPS into battery mode without load. Connect a voltmeter to the UPS output to measure the effective voltage value. By adjusting the VR3 resistor, set the voltage at the UPS output to 208 ± 2 V.

Setting the threshold voltage

Set switches 2 and 3 on the rear of the UPS to OFF. Connect the UPS to a LATR-type transformer with continuously variable output voltage. Set the voltage of 196 V at the LATR output. Turn the VR2 resistor counterclockwise until it stops, then slowly turn the VR2 resistor clockwise until the UPS switches to battery power.

Setting the charge voltage

Set the UPS input to 230 V. Disconnect the red wire to the positive battery terminal. Using a digital voltmeter, adjust the VR1 resistor to set the voltage on this wire to 13.76 ± 0.2 V relative to the common point of the circuit, then restore the connection to the battery.

Typical malfunctions

Typical malfunctions and methods for their elimination are given in table. 4, and in table. 5 - analogs of the most frequently failing components.

Table 4. Typical Back-UPS 250I, 400I and 600I Faults

Defect manifestation	Possible reason	Defect finding and elimination method
Smoke smell, UPS is not working	Input filter defective	Check the health of the MOV2, MOV5, L1, L2, C38, C40 components, as well as the board conductors connecting them
UPS will not turn on. Indicator is off	UPS input circuit breaker (circuit breaker) disabled	Reduce the load on the UPS by disconnecting part of the equipment, and then turn on the circuit breaker by pressing the contact column of the circuit breaker
	Defective accumulator batteries	Replace batteries
	Batteries not connected correctly	Check if the batteries are connected correctly
	Inverter defective	Check that the inverter is working properly. To do this, disconnect the UPS from the AC mains, disconnect the batteries and discharge the C3 capacity with a 100 Ohm resistor, ring the drain-source channels of the powerful field-effect transistors Q1 ... Q6, Q37, Q36 with an ohmmeter. If the resistance is a few ohms or less, replace the transistors. Check the resistors in the gates R1 ... R3, R6 ... R8, R147, R148. Check the health of transistors Q30, Q31 and diodes D36 ... D38 and D41. Check fuses F1 and F2
		Replace IC2
When turned on, the UPS disconnects the load	Defective transformer T1	Check the health of the windings of the transformer T1. Check the tracks on the board connecting the T1 windings. Check fuse F3
The UPS is operating on battery power even though mains voltage is present	The mains voltage is very low or distorted	Check the input voltage with an indicator or meter. If it is permissible for the load, reduce the sensitivity of the UPS, i.e. change the response limit using switches located on the back of the device
UPS turns on, but no voltage is supplied to the load	Defective relay RY1	Check the health of relay RY1 and transistor Q10 (BUZ71). Check the serviceability of IC4 and IC3 and the supply voltage at their terminals
		Check the tracks on the board connecting the relay contacts
The UPS hums and / or shuts down the load, not providing the expected backup time	Defective inverter or one of its elements	See sub-item "Inverter defective"
UPS does not provide expected backup time	Batteries are flat or lost capacity	Charge the batteries. They need to be recharged after extended power outages. In addition, batteries age quickly with frequent use or when operated in high temperature environments. If the batteries are nearing the end of their service life, it is advisable to replace them, even if the battery replacement alarm has not yet been sounded. Check the capacity of the charged battery with a vehicle high beam 12 V, 150 W
	UPS overloaded	Reduce the number of consumers at the UPS output
UPS does not turn on after battery replacement	Incorrect connection of rechargeable batteries when replacing them	Check if the batteries are connected correctly
The UPS emits a loud tone when turning on, sometimes with a decreasing tone	Defective or discharged rechargeable batteries	Charge the batteries for at least four hours. If the problem persists after recharging, the batteries should be replaced.
Batteries do not charge	Diode D8 is faulty	Check if D8 is working properly. Its reverse current should not exceed 10 μA
	Charge voltage below required level	Calibrate Battery Charge Voltage

Table 5. Analogs for replacing defective components

Schematic designation	Defective component	Possible replacement
IC1	LM317T	LM117H, LM117K
IC2	CD4001	K561LE5
IC3, IC10	74S14	Consists of two K561TL1 microcircuits, the outputs of which are connected according to the pinout on the microcircuit
IC4	LM339	K1401SA1
IC5	CD4011	K561LA7
IC6	CD4066	K561KT3
D4 ... D8, D47, D25 ... D28	1N4005	1N4006, 1N4007, BY126, BY127, BY133, BY134, 1N5618 ... 1N5622, 1N4937
Q10	BUZ71	BUZ10, 2SK673, 2SK971, BUK442 ... BUK450, BUK543 ... BUK550
Q22	IRF743	IRF742, MTP10N35, MTP10N40, 2SK554, 2SK555
Q8, Q21, Q35, Q31, Q12, Q9, Q27, Q28, Q32, Q33	PN2222	2N2222, BS540, BS541, BSW61 ... BSW 64, 2N4014
Q11, Q29, Q25, Q26, Q24	PN2907	2N2907, 2N4026 ... 2N4029
Q1 ... Q6, Q36, Q37	IRFZ42	BUZ11, BUZ12, PRFZ42

Gennady Yablonin
"Repair of electronic equipment"

Uninterruptible power supplies provide a stable power supply for stationary computers and critical electronic systems of the enterprise. An uninterruptible power supply (UPS) provides a stable supply of electricity to the devices during a short outage of the main source.

Most often, in an uninterruptible power supply, the battery requires repair, since this unit in the UPS takes over the main load. In most cases, normal wear and tear of the battery is the cause.

There are other malfunctions characteristic of UPS of all types and brands:

• Capacitors: stop working due to the drying out of the electrolyte.
• Fans: They can be affected by drying out of the lubricant.
• Inverter: very sensitive to changes in loads, voltage, and often stops functioning under conditions of unfavorable grid operation and battery failure.

Sometimes the uninterruptible power supply itself creates interference, in which case it must be equipped with filters against radio frequency and electromagnetic interference. Natural wear and tear of the unit as a result of long-term operation can also lead to the failure of the UPS.

Breakdowns of an uninterruptible power supply are very diverse, unfavorable operating conditions can also provoke a premature UPS repair - in particular, the ingress of dust into the unit case. Therefore, the place where the uninterruptible power supply is installed should always be clean.

UPS Repair Prices:

Brand Cyberpower
Model	Battery Ah	Price, rub
dx650e	4,5	1500
dx850e	7,2	1600
dl650elcd	4,5	1500
dl850elcd	7	1600
ex650e	4,5	1500
ex850e	7,2	1600
bu600e	5	1500
br850elcd	9	2200
br1200elcd	5,8	2200
ut850ei	7	1600
br1000elcd	9	2200
bs850e	7	1600
bs650e	4,5	1500
value600elcd	7	1600
value800elcd	9	2200
value1000elcd	9	2200
value1200elcd	7x2	3000
value1500elcd	9x2	4200
value2200elcd	9x2	4600
value1200eilcd	7x2	3000
value1500eilcd	9x2	4200
value2200eilcd	9x2	4600
value600ei	7,2	1600
value800ei	9	2200
value1000ei	9	2200
value400ei	4,5	1500
value500ei	4,5	1500
value700ei	7,2	1600
cp1350eavrlcd	8x2	4200
cp1500eavrlcd	8.5x2	4600
pr750elcd	7x2	3000
pr1000elcd	12x2	5800
pr1500elcd	17x2	6200
pr1000elcdrt1u	6v9ahx4	6300
pr1000elcdrt2u	7x4	5800
pr1500elcdrt2u	7x4	5800
pr3000elcdrt2u	9x4	8800
pr1500elcdrtxl2u	9x4	8800
pr2200elcdrtxl2u	9x4	8800
pr2200elcdrt2u	9x4	8800
pr3000elcdrtxl2u	9x4	8800
pr6000elcdrtxl5u	9x16	32000
pr750elcdrt1u	6v9ahx4	6400
or600elcdrm1u	6v9ahx2	3200
or1000elcdrm1u	6v7ahx4	5600
or1500elcdrm1u	6v9ahx4	6400
ols1000e	7x3	4500
ols1500e	9x3	6600
ols2000e	7x6	7800
ols3000e	9x6	13200
ols1000ert2u	7x3	4500
ols1500ert2u	9x3	6600
ols2000ert2u	7x6	7800
ols3000ert2u	9x6	13200
ols6000e	7x20	25000
ols10000e	9x20	40000
ol1000ertxl2u	9x3	6600
ol1500ertxl2u	9x3	6600
ol2000ertxl2u	9x6	13200
ol3000ertxl2u	9x6	13200
ol6000ert3ud	7x20	25000
ol8000ert3ud	9x20	40000
ol10000ert3ud	9x20	40000
ol6000ert3udm	7x20
ol8000ert3udm	9x20
ol10000ert3udm	9x20
ol6000e	7x20
ol8000e	9x20
ol10000e	9x20
ol1000exl	7x3
ol1500exl	9x3
ol2000exl	7x6
ol3000exl	9x6
Brand Ippon
Model	Battery Ah	Prices, rub
Back Office 400	4,5	1500
Back Office 600	7	1600
Back Office 1000	7.2x2	3000
Back Verso New 400	4,5	1500
Back Verso New 600	5	1500
Back Verso New 800	7	1600
Back Verso 400	4,5	1500
Back Verso 600	7	1600
Back Verso 800	9	2200
Back Comfo Pro 400	4,5	1500
Back Comfo Pro 600	7	1600
Back Comfo Pro 800	9	2200
Back Power Pro LCD Euro 600	7,2	1600
Back Power Pro LCD Euro 800	9	2200
Back Basic 650	7	1600
Back Power Pro LCD 400	7	1600
Back Power Pro LCD 500	7	1600
Back Power Pro LCD 600	7	1600
Back Power Pro LCD 800	9	2200
Back Power Pro 400	7,2	1600
Back Power Pro 500	7,2	1600
Back Power Pro 600	7,2	1600
Back Power Pro 700	7,2	1600
Back Power Pro 800	9	2200
Smart Power Pro 1000	7x2	3000
Smart Power Pro 1400	9x2	4200
Smart Power Pro 2000	9x2	4200
Smart Winner 1000	9x2	4200
Smart Winner 1500	9x2	4200
Smart Winner 2000	7x6	7800
Smart Winner 2000E	9x4	7600
Smart Winner 3000	9x6	10800
Smart Winner 1500 (2006)	7.2h2	3000
Smart Winner 2000 (2006)	9h2	4200
Smart Winner 3000 (2006)	5x8	11200
Innova RT 1K	7x3	4500
Innova RT 1.5K	7x4	5800
Innova RT 2К	9x4	7600
Innova RT 3К	9x6	10800
Innova RT 6K	5x15	21000
Innova RT 10K	9x20	36000

This is not an official offer.

Diagnostics is free. If you refuse to repair, money is also not taken for disassembling and assembling the equipment.

Repair features

The UPS is an important unit that should be trusted only by qualified technicians in the event of a failure. The consequences of unskilled intervention in the UPS device are unpredictable, since self-repair can cause:

• additional breakdowns that will increase repair costs;
• complete failure of the UPS without the possibility of recovery;
• unstable operation and UPS failures;
• fire of the UPS.

Self-repair is possible only if the battery is out of order - it will not be difficult to replace it. Attempts to troubleshoot other UPS faults, such as the board, can lead to the most dangerous consequences.

Modern uninterruptible power supplies are technologically complex and require a professional approach to repair. You can find out the cause of the UPS malfunction using special diagnostic equipment, which is available from a licensed electronics repairer.

In some cases, an uninterruptible power supply cannot be repaired - for example, if its casing is damaged by fire or a fall, water gets inside. Only the technician can reliably judge the maintainability of your UPS, as well as the possible cause of the breakdown.

You can order diagnostics and repair of uninterruptible power supplies - APC Back-UPS 500, APC Back-Up ES 700, APC Smart-UPS 1500, etc. - at the Engineer company. We have the necessary equipment and many years of experience at our disposal.

Repair of any complexity

Professionalism of employees, modern equipment, availability of spare parts and extensive practice allow us to repair the most complex devices: LCD TVs, all types of industrial equipment and microelectronics.

Availability of certified equipment

Thanks to this, even complex soldering of BGA chips using a thermal profile is available. Soldering of chips is necessary when repairing almost any electronics - from recorders to complex electronic control units of industrial equipment.

Save time

Although the laptop repair service in Moscow is very common, sometimes it is not available due to the lack of any spare parts, and the order and delivery are stretched for an indefinite period. We guarantee that our process will go faster. This is guaranteed by reliable suppliers and availability of scarce spare parts. You don't have to wait weeks for them to arrive as you did before.

Saving

Repair is always cheaper than a new purchase. Even if your TV, which is very expensive and ultra-modern, breaks down, it can be repaired for a small amount. Why give up good technique because of a small breakdown? Bring it to us, find out the cause of the breakdown and the timing of its elimination. The renovation will be carried out at reasonable prices. In this case, no prepayment is required - you pay for the DONE WORK.

Guarantee

You will receive WARRANTY DOCUMENTS that provide free repairs for repeated breakdowns.