S&C Instruction Sheet 716-504
37
Operation
Understanding the Gas-Pressure
Indicator and Safety Relief Device
Series 2000 Circuit-Switchers have sealed
interrupters containing gas under pressure.
Loss of gas pressure may result in improper
interrupting action. Low gas pressure is signaled
by a red target in the gas-pressure indicator at
the upper terminal end of the interrupter.
Figure 45 illustrates a gas-pressure indica-
tor with acceptable gas pressure.
Figure 46 illustrates a gas-pressure indica-
tor with a red target semiphore, signaling a loss
in gas-pressure.
Understanding the Optional Remote
Gas-Density Monitor
The remote gas-density monitor provides local
and remote indication of the gas density in each
interrupter in terms of percent full. The system
can be wired to provide remote indication
of the gas density of each interrupter via
three analog 0 to 1.0 mA dc outputs. The LCD
provides indication of gas density and alarms
for each interrupter. The remote gas density
monitor transmits updated measurements
approximately once per hour.
The remote gas-density monitor has three
available alarm contacts. The system provides
both local and remote indication of alarms.
Level 1 Alarm
indicates an interrupter is
leaking. The Circuit-Switcher can still be
operated, but the leaking interrupter should
be replaced promptly.
Level 2 Alarm
indicates an interrupter has
lost enough SF
6
gas that it can no longer
clear faults properly.
System Trouble Alarm
indicates a problem
with the monitoring system. A system trouble
alarm will activate when the receiver fails
to receive a signal for more than 24 hours.
The system trouble alarm will also activate
when there are approximately three months
or less of battery life remaining. At first,
a
Low Battery
alarm will appear locally.
After the battery has completely discharged,
an “Error” message will appear in place of
the percent-gas-density information, and the
system trouble alarm will signal remotely.
For complete instructions on installing,
operating, and troubleshooting the optional
remote gas-density monitor, refer to S&C
Instruction Sheet 716-530.
Inspection Recommendations
To ensure the continued proper performance,
Series 2000 Circuit-Switcher should be inspected
in accordance with S&C-recommended schedule
and procedures contained in S&C Instruction
Sheet 716-590.
Figure 45. The normal gas pressure indicator and relief device.
Figure 46. The visible “red target” gas pressure indicator.
Gas pressure indicator
Safety relief
device
Red target
(semiphore)