Bulletin No. 3020IB9814
December 1998
26
Deriving Control Power Whenever possible, derive circuit monitor control power from a stable
from Phase PT Inputs voltage source. If such a source is unavailable, the circuit monitor can derive
control power from its phase PT inputs. Due to the wide range of permissible
control power inputs, the circuit monitor can accept either L-N or L-L control
power inputs up to 240 V nominal. Using the L-L control power option
increases the circuit monitor ride-through time and enables more reliable
operation during voltage disturbances.
Referring to figures 3-12 and 3-13, complete the following steps to derive control
power from phase PT inputs:
1. Connect the Va terminal (terminal 12) to the L terminal (terminal 25).
2. For L-N control power, connect the Vn
terminal (terminal 9) to the N
terminal (terminal 27). For L-L control power, connect the Vc terminal
(terminal 10) to the N terminal (terminal 27).
3. Install protective terminal strip covers. See Appendix C for instructions.
HAZARD OF EQUIPMENT DAMAGE
When deriving control power from the phase PT inputs, the phase
PT used must have a VA rating sufficient for all connected burdens.
If the VA rating is exceeded, it could reduce the voltage transformer’s
accuracy or damage the PT.
Failure to observe this precaution can result in equipment
damage.
CAUTION
!
To Next Page
Loading...
Need help?
General