Emco EE301-T, Manual

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16. TEST MODE :
When the 'Test / Normal' switch is put in the 'TEST' mode, the PT I/P can be
simulated through the 'TEST Control'. However to prevent any undesirable
operation of the OLTC, the relays are cut off, but the lamp indications are
available.
17. TIME DELAY :
This is a variable control with variation from 10 sec. to 120 sec. The actual
setting can be made as required. The corrective action will take place only after
the set Time Delay interval is elapsed provided the voltage deviation persists
even after the set Time Delay and that the relay is not operating in UV / OV mode.
18. CONTROL RELAYS :
Connect the respective Lower, Raise, Control Fail and Under / Over voltage NO
contacts to operate the respective contactors / Alarms.
19. TPI OPERATION CHECK :
Keep the Test/Normal Switch of TPI in Normal mode & connect Min., Max. &
Wiper from OLTC to the Rear Panel Terminal Block. Change the tap position from
1 to maximum tap and check whether TPI reads correctly.
Keep the TPI "Test/Normal" switch in "Test" mode & check whether
display reads "88".
FUSE REPLACEMENT :
1 After switching power-on, the display indication must come. If it does not come,
check whether AUX. fuse on the rear panel is properly tightened. If the
instrument still does not work, unscrew the fuse & check if it is open. Replace
it by another fuse of 300mA (20mm).
Once again ensure that the fuse is not loose. The instrument should turn on
now. If the fuse keeps on blowing repeatedly or the instrument does not work
inspite of good fuse, proceed to identify the faulty PCB as given in fault finding
procedure VII.
2 Connect the PT supply and put the Test/Normal switch in Norrnal position. If
the Instrument is turning on but you are continuously getting 'R’ and ’UV’
indication, check whether PT fuse is loose. If the condition persists even after
tightening PT fuse, remove the same and replace by another 100mA (20mm)
fuse. If ‘UV’ and ‘R’ indication still persist, proceed to identify the faulty PCB as
given in fault-finding procedure VIII.
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