INSTALLATION cont.

WIRING cont.

Terminal connections shown in Figure 4 are for a standard

SPDT switch. Actuating the switch closes one circuit and

simultaneously opens the second circuit. In this diagram,

circuit between contacts 4 and 5 is made and circuit

between contact 5 and 6 is broken at low liquid level. At

high level, circuit between contacts 4 and 5 is broken and

circuit between contact 5 and 6 is made.

DIFFERENTIAL ADJUSTMENT

The amount of level travel between “switch on” and “switch

off” can be reduced from the maximum factory setting by

raising the lower set of jam nuts. Minimum free play (differ-

1. Disconnect wiring from supply side of switch mecha-

nism and electrical conduit or operating medium line

connections to switch housing.

2. Perform system shut-down as required to relieve pres-

sure from tank or vessel and drain off liquid “head”

above control mounting position. Allow unit to cool.

3. Remove switch housing assembly by loosening enclos-

ing tube nut located immediately below housing base.

Refer to Figure 8 on page 7.

4. With switch housing removed, jam nuts and magnetic

sleeve are now accessible, as shown in Figure 6.

Raising the lower jam nuts will reduce the differential. As

the first step in any adjustment procedure, the position

of the upper and lower jam nuts should be established.

NEVER CHANGE SETTING OF UPPER JAM NUTS AS

THEY SUPPORT FLOAT ASSEMBLY SO THAT IT CAN-

NOT TOUCH BOTTOM OF CHAMBER.

5. Loosen and remove upper jam nuts, guide washer, and

magnetic sleeve. Lower jam nuts may now be adjusted

to reduce the differential.

NOTE: Be certain to tighten jam nuts securely after adjustment.

6. Replace magnetic sleeve on stem and position upper jam

nuts to their original setting. Lock upper jam nuts to guide

washer.

7. Reassemble control in reverse of steps 1 through 3, previ-

ously described.

8. Test switch actuation by varying liquid level in tank or vessel.

Figure 4

Figure 5

Figure 6

CAUTION: Before attempting any work on the control,

be certain to pull disconnect switch or otherwise assure

that electrical circuit(s) through control is deactivated.

Close operating medium supply valve on controls equip-

ment with pneumatic switch mechanisms.

Receiver

From Condenser

To Evaporator

INSTALLATION SHOWING LEVEL CONTROL (OR ALARM) ON A RECEIVER

Desired

Actuating Level

Insulation

End View

Side View

Chamber mark indicates

actuating level

DO NOT Insulate

Switch Housing

Mount control so mark on chamber corresponds to level desired

in vessel. When control is used on a low temperature liquid,

chamber and connection lines should be insulated as shown to

prevent “boiling” in the float chamber and false level indications

4 RED

Assembly B

Load

Load

Line

Ground

GREEN

Internal

Circuit

Close on

Falling Level

Close on

Rising Level

Common

5 YELLOW

6 BLUE

Jam nuts.

Slight play (gap)

must be allowed

(.03" [.8 mm] typical)

Differential gap

Magnetic sleeve

3