- Do not replace any of the semiconductor fuses in this unit with Gould/Shawmut form 101 fuses. The Gould/Shawmut fuses do not have a comparable I²t rating and may cause damage or fire in the unit.
- The charger equalize voltage should be set at no more than 29V, 56V, 140V or 280V when the inverter is running. Operation at higher voltages may blow an inverter fuse.
Note: Inverters with auto restart will not start if battery breaker is not closed. Bypass is not available. The front display panel must be functioning for inverter to start. The Inverter also will not start if RL1 on motherboard is not plugged in properly or the battery voltage is lower than 25V for 24V battery (12 cells), 50V for 48V battery (24 cells), 125V for 120V battery (60 cells), or 250V for 240V battery (120cells) or 234V for 197 to 261V battery.
CHECK: FU4 (FU5), battery voltage, SCR4 & 5 (SCR6 & 7) gate signals, voltage between wire #1 and wire #14 (#18), on inverter board voltage from TP9 to board ground. Note above.
SOLUTIONS or EXPLANATIONS: If Fuses are blown, check associated SCR's and Diodes before replacing fuse. Then perform a "BUZZ DOWN". If no gates, check the inverter board.
For inverter to run the following must exist on the inverter board:
a & b. No 12V and No C15 voltage, check wire connections to mother board at J2-2,3 and J2-7,9
On inverters with auto-start, if there are gates on SCR4 and 5, but no voltage at wire #14 (18), check RL1 on the mother board and check the gate wires to SCR8 (9). If the voltage across D7 on the mother board is equal to the DC bus, check R42 to R45, D8, D9 and continuity of RL1 socket on the mother board. Replace RL1. Replace the mother board.
CHECK: CB6 or FU6(7, 8) , Check C10(C11) for shorted capacitor.
SOLUTIONS or EXPLANATIONS: If the fuses are blown, check the associated SCR's in the static switch before replacing. Replace static switch gate board (20060000). Replace Static Switch Board (200300X). Replace shorted capacitor.
CHECK: CB6 or FU6(7, 8) , Check for bulged C10 (C11) or bad connections to C10 (C11). Check the voltage with True IRMS DVM. If a 3 phase unit, check FU4 and FU5.
SOLUTIONS or EXPLANATIONS: If the fuses are blown, check the associated SCR's in the static switch or inverter bridge before replacing. Replace bulged C10 (C11).
CHECK: Check for Bypass input (voltage and frequency) at static switch SCR's, Check Bypass input breaker, with meter measure difference voltage from Inverter to bypass on static switch SCR's.
SOLUTIONS or EXPLANATIONS: If Bypass is available, but not within +/- 10% in voltage and/or +/- 0.6 Hz, or the frequency is changing faster than 1Hz/second, the unit is not going to transfer. Correct the bypass. If Bypass is available and the different voltage is continuously <35V, but Static Switch will not transfer to inverter, replace "Static Switch Control board". If unit will transfer but "IN SYNC" LED does not light, check and replace LED. If Bypass is within the limits and difference voltage >35v or changing, check the motherboard connector J11 and reconnect. Check the phase rotation of bypass and reconnect bypass input for same rotation as inverter (3 phase only). Check the frequency of the inverter board oscillator TP8, adjust it with the oscillator potentiometer on board. Replace the "Inverter Control Board".
CHECK: Static switch SCR's (SCR10 - SCR13, SCR14 - SCR17, and SCR18 - SCR21) for shorted device. Check the static switch gate boards for damaged components.
SOLUTIONS or EXPLANATIONS: A shorted SCR or a bad gate board will tie the Bypass terminals of the static switch to the inverter. This causes the inverter to chase it's tail when the sync circuit trys to sync to itself.