8.19
Date Code 20060320 Instruction Manual SEL-311C Relay
Breaker Monitor and Metering Functions
Station DC Battery Monitor
Operation of Station
DC Battery Monitor
When AC Voltage Is
Powering the Relay
If the SEL-311C has a 125/250 Vac/Vdc supply, it can be powered by ac
voltage (85 to 264 Vac) connected to the rear-panel terminals labeled POWER.
When powering the relay with ac voltage, the dc voltage elements in
Figure 8.9 see the average of the sampled ac voltage powering the relay—
which is very near zero volts (as displayed in column
Vdc in event reports).
Pickup settings DCLOP and DCHIP should be set off (DCLOP = OFF,
DCHIP = OFF) since they are of no real use.
If a “raw” event report is displayed (with the EVE R command), column
Vdc
will display the sampled ac voltage waveform, rather than the average.