M90 & M90L Service Manual Uninterruptible Power Supply Table of Contents General Information..................4 Getting Started..........................4 Important Safefty Instructions......................4 Electronic Specifications................5 Environmental Parameters......................6 Functional Block...................7 Working Pricipal of the Major Functional Block................8 Switch Power Supply........................9 PFC/Booster............................9 Inverter............................9 Charger............................10 EMI Board............................10 Function Explanations for Each PCBA............11...
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M90 & M90L Service Manual Uninterruptible Power Supply Bypass Mode..........................13 Line Mode.............................14 Battery Mode..........................15 Battery test Mode.........................15 Fault Mode............................15 Converter Mode..........................16 ECO Mode.............................17 Shutdown Mode...........................17 Trouble Shooting..................17 LCD Panel Display Pattern Definition....................1 Trouble shooting for warning icon in LCD display...............17T rouble shooting for fault codes in LCD display................18...
Getting started This manual is for the M90 and M90L UPS. It can help service person perform the basic maintenance and repair service. This manual only focuses on the service section, so you should get the basic operation of the UPS from the user manual, and make sure you had read and understood the user manual before reading the manual.
M90 & M90L Service Manual Uninterruptible Power Supply Electronic Specifications Model Power kVA Power kW Mains Input (Rectifier input Line) Input Topology Three Phase, Neutral + Ground Nominal Voltage 208/220 Voltage Range (Full 156 ~ 253 100% load; Load) Voltage Range (Derating) 121V~ 253V with <70% Load...
M90 & M90L Service Manual Uninterruptible Power Supply Efficiency > 92.5 % at over 50% load (Power Module Measurement) Model Battery Nominal Voltage +/- 120V Battery Charger Floating Voltage 2.3V/cell Boost Charging 2.35V/cell Temperature compensation -3mV/°C/cell (Option) Charger Voltage < 1%...
M90 & M90L Service Manual Uninterruptible Power Supply Dimensions (WxHxD) 490 x 130 (3U) x 736.5 mm Net Weight 34.5 kg Functional Block As a true online UPS, the product applies a double conversion topology, comprising functional blocks as shown in the figure below.
M90 & M90L Service Manual Uninterruptible Power Supply The Inverter block is the output stage of the UPS and used to convert DC power from the BUS capacitor to sine waveform output power. When the utility is within the acceptable range, the UPS will provide power directly from the utility input and the Rectifier and PFC will be executed at the same time.
M90 & M90L Service Manual Uninterruptible Power Supply The figure above is a flyback converter. When Q5 is on, all rectifier diodes (D2/D3/D4/D9) are on open status and all output capacitors supply currents to the load. The primary coil of the transformer will become a pure inductor and the primary current will linearly increase to store energy in the coil.
M90 & M90L Service Manual Uninterruptible Power Supply Neutral Point Clamped Inverter Charger The function of charger is to charge and maintain the batteries at fully charged condition. The charger charges the batteries with a constant current at initial stage. At the same time, the battery voltage keeps increasing until reaching the constant charge voltage point.
M90 & M90L Service Manual Uninterruptible Power Supply Function explanations for each PCBA PCB information of Power module Item PCBA Name PCBA serial number Quantity Remark STS Main Board 71-301695-xxG Communication Board 71-300826-xxG SPS Board 71-301616-xxG Interface Board 71-300869-xxG EMI Board...
M90 & M90L Service Manual Uninterruptible Power Supply EMI board The EMI board can prevent the UPS from external electronic/magnetic noise generated by other electronic sys- tems, and also prevent other systems from the noise generated inside of the UPS system.
M90 & M90L Service Manual Uninterruptible Power Supply Shutdown Mode UPS Mode Description Shutdown Mode A:Off, B:Off, C:Off, D:Off, E:Off, F:Off, G:Off Trouble Shooting This section describes how to find the troubles when UPS is abnormal. We suggest you to follow the service procedure below: 1.
M90 & M90L Service Manual Uninterruptible Power Supply Trouble shooting for fault codes in LCD display When the UPS is fault, it will transfer to Fault mode. Representation in display Explanation Conduct item Fault! Bus Over Voltage DC bus voltage is too high...
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M90 & M90L Service Manual Uninterruptible Power Supply Fault! TR Inverter Voltage T-R inverter Output is shorted Shutdown and remove this power Short module Check IPOP and Inverter PCBA Fault! Inverter R Negative R phase inverter Output Shutdown and remove this power...
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M90 & M90L Service Manual Uninterruptible Power Supply Warning! Communicate CAN communication error Shutdown and remove this power Can Fail module Check Control and Parallel PCBA Warning! Over Load The load devices are demanding Check over load have >100% more power than the UPS can supply.
M90 & M90L Service Manual Uninterruptible Power Supply Repair In this section, some debug skills are listed to help you finding the failed components and problems as soon as possible. Before proceeding the following steps, we strongly suggest to read previous section for trouble shooting first.
M90 & M90L Service Manual Uninterruptible Power Supply R400,R399,R398,R404,R401,R403,R40 Resistance 49.9kΩ±0.1% Value change 8,R405,R407 R323,R319,R321,R318,R344,R315 Resistance 402kΩ±0.1% Value change R389,R402,R406 Resistance 200KΩ±0.1% Value change R331,R332,R333,R355,R334,R293,R33 Resistance 750KΩ±0.1% Value change 5,R296,R328,R329,R330,R354,R346,R3 06,R347,R308,R325,R326,R327,R353,R 342,R343,R356,R357 R24,R23,R33,R45,R18,R16, R40,R39,R1 Resistance 47Ω±1% Value change 7,R15,R28,R42,R8,R9,R32,R31,R54,R5 3,R57,R65,R48,R49,R60,R61...
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M90 & M90L Service Manual Uninterruptible Power Supply R17,R49,R13,R45,R9,R29,R5,R25,R1 Resistance 162kΩ±0.1% Value change ,R21, R20, 52,R16,R48,R12,R32,R8,R2 8,R4,R24, R18,R19,R50,R51,R14,R46,R 15,R47,R10,R30,R11,R31,R6,R26,R7,R 27,R2,R22,R3,R23 Note: If IGBT is OK, but the parameter is not close to the reference value, it is very possible that the correspond- ing driver is damaged, so please try to change the IGBT driver component.
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M90 & M90L Service Manual Uninterruptible Power Supply Major parameters of SPS Board section The most likely problems occur on Inverter board section including: broken MOSFET, broken Diode , and broken MOSFET driver resistor. SPS Board Checked components Instrument function...
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