Motor Overload Protection - Pentair MYERS Serie Manual De Uso

MOTOR OVERLOAD PROTECTION

All single phase motors have built-in automatic reset
overload switches fastened directly to the motor windings.
All 3 phase motors must be installed with magnetic starters
having 3 leg overload protection.
HOW TO SET CONTROLS AND START
SIMPLEX SYSTEMS
1. Automatic systems – These systems have the MLC,
MFLC, or ALC switches mounted on the pump, so pump
is installed in the sump and motor cord is plugged into
GROUNDED receptacle. For sealed sump cover, power
cord is brought through a split rubber plug in the sump
cover.
2. Where 2 "mercury" controls are used the turn on control
is set 3" to 6" above top of motor, and the turn-off control
is set about 6" to *' above bottom of sump. If a high level
alarm control is used it is set about 6" above upper
control. If sump depth will not allow these settings closer
spacing can be used.
3. Where ALLC or AWS-1 controls are used the
DISPLACEMENT WEIGHTS are set so that turnon
weight is 4" to 6" above top of motor and lower weight is
set about 6" above sump bottom.
4. Repeat this operation with one pump off which will
duplicate a failed pump condition. When the level
reaches the override control the pump that is turned on
should start and run and pump down sump level.
5. To check high level alarm, again turn both switches to
OFF and fill sump until level is above the alarm control.
Turn switches to Auto position and ALARM BUZZER
should sound and alarm light should come on. When
level drops below the alarm control buzzer should stop.
6. If pumps operate as described then set both H-O-A to
Auto and pumps are ready to operate automatically.
7. If pumps do not operate properly then check as
described for simplex systems. See page. 13.
NEVER WORK ON PUMPS OR CONTROL
BOXES UNTIL CIRCUIT BREAKERS ARE TURNED OFF.
Always have a qualified ELECTRICIAN make electrical
connections and service checks.
SPECIAL INSTRUCTIONS FOR THREE
PHASE PUMPS
1. Only qualified persons shall conduct
services and installations of this pump. The pump
must be wired by a qualified electrician, using an
approved starter box and switching device.
Risk of electric shock. Do not connect
conduit to pump
2. Three phase pumps are always installed with control
boxes having magnetic starters with 3 leg overload
protection. DO NOT TRY TO RUN THREE PHASE
PUMPS DIRECTLY ACROSS THE LINE.
3. To Connect Pump: Run wire from pump to the bottom
of control box or appropriate junction box suitable for
enclosing splice connections. A hole must be cut into the
control box for the wires. With power to control box off,
connect green (ground) line to ground lug. Connect black
(power) wires to power lead terminals. Make sure that all
wires are inside control box and not in a position to be
pinched or shorted when the door is closed. See wiring
diagrams, page 8.
4. All three phase motors can run either direction,
ROTATION can be changed by interchanging any two
line leads at magnetic starter. BE SURE CIRCUIT
BREAKER IS OFF BEFORE MAKING THIS CHANGE.
To find if rotation is correct operate pumps and check
delivery operation. If flow and head is low (refer to pump
curves shown in this manual) the rotation is wrong.
With duplex pumps check operation of both pumps.
All pump impellers either single or three phase must
turn counterclockwise when looking into pump inlet. If
uncertain of rotation, TURN OFF POWER and lift pump
from basin with cord connected and lay pump on side
so impeller can be seen. Turn on power and start pump
using hand position of H-O-A switch. Turn on and off
fast so that coast of impeller can be seen. NEVER PUT
HAND OR FINGERS ON THE IMPELLER. Interchange
any two line leads at the magnetic starter to change
rotation.
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