6
1.2.4 Standard Alarms
Four alarms are included as a standard feature of the ESCR. The included alarms are a High DC Voltage, Low
DC Voltage, Charger Failure and an AC Failure alarm. Each alarm includes a form C contact enabling the
customer to connect remote annunciators. The Alarm contacts are rated for 10 Amps at 28 VDC.
A
Charger Failure Alarm occurs if the charger is not able to regulate the output voltage. This alarm relay
stays latched in, even after the alarm conditions clear; until the ESCR unit is reset.
The AC Failure Alarm will trigger (after a preset delay) when the AC power to the unit is lost. The AC
Failure alarm is Fail-Safe Relay alarm. The relay will de-energize on failure condition. The alarm will
automatically reset when AC power is restored to the unit. When AC power is lost the front panel display
and
indicators will remain powered by the connected batteries. Refer to the example for AC Fail alarm
connections Figure-7.
The alarm contacts for AC Fail alarm displayed in Figure 5 and figure 6 are shown in De-Energized state.
The
High DC Voltage Alarm will trigger when the DC output voltage of the ESCR exceeds the preset high
voltage alarm value, and will reset when the DC output voltage returns to normal. The high voltage value is
adjustable and can be set in Configure Mode.
The
Low DC Voltage Alarm will trigger when the DC output voltage of the ESCR falls below the preset low
voltage alarm value, and will reset when the DC output voltage returns to normal. The low voltage value is
adjustable and can be set in Configure Mode.
Alarm Logic
Alarm Logic
AC Fail
De-Energize on Failure
Charger Fail
Energize on Failure
High DC
Energize on Failure
Low DC
Energize on Failure
Table 5-Alarm Logic
Figure 5 – Control/Alarm Card S2A-349