AEC IST7 20kVA, Руководство пользователя, Страница: 76 / 86

2 Overview
AEC UPS IST7 10-30 KVA
User Manual
68
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Troubleshooting
3.4.1 Common Abnormal Phenomena Diagnosis
If the UPS works abnormally after start, please refer to Table1.1 to find possible reason. Meanwhile,
check whether the fault is caused by external environment, such as temperature, humidity is not
accordance with the requirement or overload.
Table1.1only includes some simple diagnosis. If the diagnosis is not clear, or not sufficient to solve the
problem, please contact with local agency or dealer to deal with.
Table1.1 Troubleshooting
NO Abnormal phenomena Possible reason
1 Mains normal, but UPS
works in battery inverting
status, the buzzer beeps
intermittently.
Each connection point, socket of grid feed circuit is not so good,
which causes the AC power supply input unblocked.
2 After installation, close
breaker or switch of
power supply, it will fuse
the fuse or trip off.
The three-phase input wires are wrongly connected, such as
neutral wire and ground wire or live wire and grounding (case) is
wrongly connected or the three-phase output wire is wrongly
connected.
3 After startup, the UPS
outputs 220V AC power,
but the UPS works in
bypass status.
1. The load it too large and exceed the rated output capacity of
the UPS. It needs to reduce load or select a UPS with larger
output capacity.
2. If it is temporary bypass caused by the impact of load startup,
and it can recover to normal automatically, that is normal.
4 The UPS output normally
after startup, but once turn
on load, the UPS stop
outputting immediately.
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The UPS is serious overload or the output circuit is
short-circuit. It is necessary to reduce load to proper capacity
or find the reason of short-circuit. Common reason is output
socket is short circuit or input short circuit caused by device
damage.
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The load is not started according to the sequence from
large power device to small power device. You should restart
the UPS. After the UPS run stably, start the load according to
the sequence from large power device to small power device.