External Transformer - ABB ATS021 Installation And Operating Instructions Manual

7. Using automatic transfer switch ATS021
Alarm
A red Alarm LED signals an external alarm (switching logic disabled or status of both breakers is closed).
Alarm status is explained in the table below.
Alarm Status
External alarm (logic locked):
- Both DI1 and DI2 active
- DI3 inactive
Switching logic alarm
No alarm
Table 7.2 Alarm status indication
When Alarm LED is ON or blinking, turn the Lim rotary switch to MAN positon, check
the state of the automatic transfer switch and repair the possible fault situation before
resetting the alarm. The automatic transfer switch is resetted by pushing the RESET
key.
Auto
A green Auto LED signals the automatic or the manual mode. When the ATS021 is in automatic mode,
the Auto LED is ON. When the device is in manual mode, the Auto LED is OFF. In test sequence the Auto
LED is blinking.
Power
A green Power LED signals the power status. When power is ON, the Power LED is ON. The ATS021 will
remain in a standby state at least one minute after power failure. A blinking Power LED indicates standby
mode.

7.2.4 External transformer

External transformer must be used when
N-line is not connected
The transformer has to fulfi l the following requirements:
Transformer has to be Main to Phase Voltage Transformer
Transformer has to be isolative
Effective value has to be 40 VA
Installation and operating instructions, ATS021
LED Indication
ON
Blinking
OFF
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