2
Signet 8450-3 Pressure Transmitter
3. Electrical
Connections
Caution:
Failure to fully open terminal jaws before removing wire may permanently damage instrument.
Wiring Procedure
1. Remove 0.5 - 0.625 in. (13-16 mm) of insulation from wire end.
2. Press the orange terminal lever downward with a small screwdriver to open terminal jaws.
3. Insert exposed (non-insulated) wire end in terminal hole until it bottoms out.
4. Release orange terminal lever to secure wire in place. Gently pull on each wire to ensure a good connection.
Wiring Removal Procedure
1. Press the orange terminal lever downward with a small screwdriver to open terminal jaws.
2. When fully open, remove wire from terminal.
Wiring Tips:
• Do not route sensor cable in conduit containing AC power wiring. Electrical noise may interfere with sensor signal.
• Routing sensor cable in grounded metal conduit will help prevent electrical noise and mechanical damage.
• Seal cable entry points to prevent moisture damage.
• Only one wire should be inserted into a terminal. Splice double wires outside the terminal.
• If your system uses a single sensor, it must be located within 400 ft. (122 m) of the transmitter.
• If your system uses two sensors, the total length of cable connected to the transmitter is limited to 400 ft.
• The 3 conductors from a dual-sensor system can be tied together and then a single set of wires continued on to the transmitter.
• For best performance, ground the sensor SHIELD wire to a local earth ground at a point near the sensor.
(Experiment with connecting the sensor shield wire to different local ground points to identify best signal quality.)
10
9
8
7
6
5
4
3
2
1
16
15
14
13
12
11
Output 2-
Output 2+
Output 1-
Output 1+
Loop 2-
Loop 2+
System Pwr
Loop -
System Pwr
Loop +
AUX
Power -
AUX
Power +
Snsr 2 Gnd
(WHITE)
Snsr 2 IN
(RED)
Snsr 2 V+
(BLACK)
Snsr 1 Gnd
(WHITE)
Snsr 1 IN
(RED)
Snsr 1 V+
(BLACK)
2
1
1
15
S
D
2
_
+
Internal open-collector
output circuit
Outputs
Isolation
Terminals 11-16: Dual digital sensor inputs
See next page for more information.
Terminals 3-4: Primary Loop Power
12-24 VDC ±10% system power and current loop connections.
SINGLE SENSOR system MUST use terminals 3-4.
Terminals 5-6: 12-24 VDC ± 10%
Power and current loop connections for second sensor.
• Maximum loop impedance:
50
Ω
max. at 12 V
325
Ω
max. at 18 V
600
Ω
max. at 24V
Terminals 7-10: Open-Collector Outputs
• Two transistor outputs programmable as High or
Low alarm with adjustable hysteresis
• Outputs can be disabled (Off) if not used
Terminals 1-2:
Auxiliary power is used
only if two sensors are connected to the
transmitter.
