Enatel DC System Manual
Page
15
of
26
Model: RWxxx
Version: 3.6
contacts are isolated from the rectifiers’ internal circuitry. Do NOT connect AC supply to
the relays.
When the rectifier is operating normally (ie with no fault, or abnormal conditions) the
relay outputs designated NC will be connected to the common terminal, and the relay
outputs designated NO will be open circuit. Upon an alarm condition occurring the NO
contacts will be connected to the common terminal, and the NC contacts will be open
circuit.
The internal alarm card is powered from the batteries connected to the rectifier. This
allows the alarm card to operate correctly even when the mains have failed.
If the rectifier does not have a battery connected and the mains fails, then the Mains Fail
relay still reflects the state of the mains, however the Rectifier Fail alarm, Rectifier Off
Normal and the Low Volts alarms will also activate.
N
OTE
: the Mains Fail Relay has its own “Common” connector, but all the other alarm
outputs share a “Common” contact.
3.8
Rectifier Fail/Mains Fail
The Mains Fail Alarm is activated while the mains power is not present.
The Rectifier Fail Alarm can be configured to activate when the mains has failed (as well as
when the Rectifier Fails). Alternatively, the Rectifier Fail can be configured to not activate if
the mains fails, so that you can remotely determine if the problem is the mains failure or a
rectifier failure.
To select between the two options set the jumper located on the rear of the rectifier. The
parameters for the Alarm Output Volt Low and High setting can be adjusted by the
trimpots next to the jumper. See
Figure 6: Alarm Configuration
3.8.1
Rectifiers in Parallel
The internal alarm cards of multiple parallel rectifiers can be connected in parallel so that
the alarm condition can be reported if any alarm is triggered in any rectifier.
When rectifiers are connected in parallel (and load sharing), the alarm outputs on the
rectifiers give the status of all the units in parallel. This means that you only need to
connect one alarm card to the alarm circuitry when the rectifiers are connected in parallel.
