961-20A0-010 Datasheet, PDF (6/36 Pages) Magnetrol International, Inc. – Ultrasonic Single and Dual Point Level Switches

2.4 Wiring
Wiring for Model 961/962 level switches is different for all
four versions. These switches are available as 4-wire, line-
powered units with 5-amp relays, or as 2-wire loop-pow-
ered units with mA current shift output. Determine which
version you have from the table below and proceed to the
proper wiring section.
Model
961
961
962
962
Input
Line-powered
Loop-powered
Line-powered
Loop-powered
Output
5 amp relays
Current shift
5 amp relays
Current shift
Wiring Information
Proceed to section 2.4.1
Proceed to section 2.4.2
Proceed to section 2.4.3
Proceed to section 2.4.4
Malfunction
SPDT Relay
Ground
Level DPDT
Relay
Input
Power
NC C NO NC C NO NC C NO
MALF RELAY
MALF
TEST
WET MALF
FAULT LEVEL
Hi I
Lo J
MODEL 961
L1
L2
TIME
DELAY
LEVEL
TEST
Figure 6
Model 961 Line-Powered Wiring
2.4.1 Model 961 Line-powered Wiring
Power and relay wiring connections are suitable for
12–24 AWG wire.
Caution: OBSERVE ALL APPLICABLE ELECTRICAL CODES
AND PROPER WIRING PROCEDURES.
1. Make sure the power source is turned off.
2. Unscrew and remove housing cover.
3. Pull power supply and relay wires through the conduit
connection.
4. Refer to Figure 6. Connect power leads to proper terminals.
Model 961 is available for AC power (102 to 265 VAC) or
for DC power (18–32 VDC)
a. AC Power – Connect “hot” wire to terminal marked L1
and the “neutral” wire to the terminal marked L2. The
green head screw should be used for grounding.
b. DC Power – Connect wires to terminals (+) and (-) on
the terminal block. The green head screw should be
used for grounding.
5. Connect desired relay wiring as shown in Figure 6.
6. Prevent moisture seepage into housing by installing an
approved seal drain fitting in the conduit run leading to
the unit.
7. Wiring is complete. Replace housing cover.
Caution: In hazardous areas, do not power the unit until the
conduit is sealed and enclosure cover is screwed
down securely.
NOTE: Housing must be grounded via green head ground screw in
the base of the housing.
6
51-646 Echotel^® Model 961 & 962 Ultrasonic Level Switches