Electrical Schematic

PAGE 13

Start Relay (a.k.a. Potential or Voltage Relay)…

1) Physical Inspection – A faint click from inside the control box can be heard very shortly after the

submersible pump motor starts, i.e. the relay contacts should be closed during the initial starting cycle,

but should open (faint click) as the motor comes up to speed. If the relay “chatters”, i.e. clicks quickly

and repeatedly, the supply voltage could be low. The start relay is designed to operate ONLY on 230-volt

systems. If the submersible pump attempts to start, but is unable to do so or if there is a humming sound,

check the relay to see if the contacts are damaged or its coil opened.

Note - Sticking relay contacts (contacts that will not open as described previously) could be damaged from

a defective start capacitor bleed resistor.

2) Test the Start Relay – Disconnect wiring from the start relay.

a) Test the relay coil using an ohmmeter- Set the ohmmeter scale to R x 1000. Connect the ohmmeter test

leads to #2 & #5 on the relay.

Coil resistance correct reading: 4.5 – 7.0 (4,500 to 7,000 ohms).

b) Test the relay contact using an ohmmeter- Set the ohmmeter scale to R x 1. Connect the ohmmeter test

leads to #1 & #2 on the relay.

Contact resistance correct reading: Zero.

Note- relay contacts are normally closed and measured resistance should be zero (0 ohms). Higher

resistance readings indicate deterioration of the contacts.

Control Box Wiring Diagram

230 V - 60 HZ

AUGUST 2014

1/2, 3/4 & 1 HP

2 5

B (MAIN) Y R(START) L2 L1

MOTOR LEADS LINE LEADS

GND

GREEN

GND

GREEN

RELAY

START CAPACITOR

with

bleed-resistor

BLACK

YELLOWYELLOW

RED

ORANGE