RKI Instruments GD-K77D - Manual (Page 18)

13 • Installation Model GD-K77D Operator’s Manual
Power Requirements
External Alarm
The Model GD-K77D can be used to control an external buzzer or alarm light. The Model
GD-K77D ‘s external alarm contacts are rated for 0.5 A @ 125 VAC, 1A @ 30 VDC, and
0.5 A @ 60 VDC. Use the alarm contacts on the Model GD-K77D to control only low
power devices. If heaver loads or inductive loads need to be controlled, use a slave relay
to accommodate the load. A CR circuit device (or Spark Killer) should be installed to
protect the alarm contacts if there is any question about the load. When driving a slave
relay, use a Spark Killer since the slave relay is an inductive load.
Figure 4: CR circuit for Alarm Relay
Table 2: Power Requirements for the Model GD-K77D
Power Voltage DC-24V +/- 10% (Terminal Voltage)
Power Failure Tolerance (Time) Approximately 10 milliseconds. After a power failure
of 10 milliseconds, the Model GD-K77D re-starts.
To ensure continuous operation, install a standby bat-
tery.
Requirements Do not connect power to the Model GD-K77D con-
taining a high power load or with high frequency
noise.
If noise is present, use a line filter to separate the
power from the noise source.
When rack-mounting the Model GD-K77D in an area
with restricted ventilation, allow for adequate ventila-
tion by mounting fans near the unit.