Gorman-Rupp Pumps S4C65-E10 460/3 861279 thru 1142084 - Manual (Page 35)

TROUBLE POSSIBLE CAUSE PROBABLE REMEDY
PUMP FAILS TO
START, OVERLOAD
UNIT NOT TRIPPED
(MANUAL MODE)
OVERLOAD UNIT
TRIPS
CONTROL BOXES OM--04136
TROUBLESHOOTING PAGE D -- 1
TROUBLESHOOTING --- SECTION D
Review all SAFETY information in Section A.
The electrical power used to operate
this control box is high enough to cause
injury or death. Obtain the services of a
qualified electrician to troubleshoot,
test and/or service the electrical compo-
nents.
Many of the probable remedies listed in the troubleshooting chart below require use of electrical test instru-
ments; for specific procedures, see
Electrical Testing at the end of the troubleshooting chart.
When troubleshooting, also refer to the technical information accompanying the pump and optional equip-
ment.
Power source incompatible with control Correct power source.
box.
No voltage at line side of circuit beaker. Check power source for blown fuse,
open overload unit, broken lead, or
loose connection.
No voltage at line terminals on bottom Check power source for blown fuse,
of overload unit in control box. open disconnect, broken wire, or
loose connection.
Low or high voltage, or excessive volt- Measure voltage at control box.
age drop between pump and control Check that wiring is correct type, size,
box. and length. (See Field Wiring
Connections,Section B).
Power input phases not If imbalance exceeds 1 percent,
balanced. notify power company
Control box not compatible with pump. Electrical data on control box and
pump name plate must agree. Re-
place control box if not in agreement.
Foreign object locking impeller or Remove foreign material or replace
bearing frozen. damaged bearing. If bearing is
damaged, check for water in motor
housing.
Motor windings short-circuited. Check motor windings with
ohmmeter.