16 • T3A Transmitter
3. Feed the power and 4-20 mA signal wires through the T3A’s power hub and into the
enclosure.
NOTE:
Wiring power to the device is the
ONLY
requirement for the T3A to operate. With
power, the unit will function normally, indicating the presence of toxic gas at the
sensor and providing the gas level reading on the display screen. To utilize the added
functionality of the device, additional wiring is necessary. If a controller is not used,
the T3A can be powered from any +12 to +35 VDC power supply that is capable of
supplying at least 250 mA.
4. Locate the power terminal block on the control board and complete the following (see
Figure 5).
•
Connect the power (GRAY) wire to the
VDC
+
terminal.
•
Connect the ground (BLACK) wire to the
VDC -
terminal.
•
Connect the signal (GREEN) wire to the
4-20 mA (S)
terminal.
CAUTION:
If shielded cable is used, leave the cable shield’s drain wire disconnected and
insulated at the T3A. You will connect the opposite end of the cable’s drain wire
to the controller’s chassis (earth) ground.
5. Route the cable or wires leading from the T3A through one of the conduit hubs at the
controller housing.
CAUTION:
Do not route power and T3A wiring through the same controller conduit hub.
The power cable may disrupt the transmission of the T3A signal to the
controller.
6. Connect the wires to the applicable detector terminal strip at the controller as shown in