
16 • VOC Pro Transmitter
3. Feed the power and 4-20 mA signal wires through the VOC Pro’s power hub and into the
enclosure.
NOTE:
Wiring power to the device is the
ONLY
requirement for the VOC Pro 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 VOC Pro 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 VOC Pro. 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 VOC Pro through one of the conduit hubs at the
controller housing.
CAUTION:
Do not route power and VOC Pro wiring through the same controller conduit
hub. The power cable may disrupt the transmission of the VOC Pro signal to the
controller.
6. Connect the wires to the applicable detector terminal strip at the controller as shown in