M2A Transmitter Operator’s Manual
33
WARNING:
To maintain the explosion proof classification of the M2A, a conduit seal must be used within
a certain distance of the junction box conduit hub used for wiring to the controller, as
outlined in the table below.
7. Guide multi conductor shielded cable or cables or wires in conduit through the conduit port on the left side
of the junction box. The number of cables or wires needed will depend on whether the M2A is wired to a gas
monitoring controller or just to power, whether any relays are used, and whether the Modbus output is used.
WARNING:
If the top conduit port is used for wiring, be sure to seal the threads to ensure water does not
enter the junction box. A conduit seal, which is normally required to maintain the junction
box’s hazardous location rating, will also help to prevent water from entering through the top
port.
NOTE:
If the M2A is being wired to a PLC or DCS device, see “Appendix B: PLC and DCS Device Wiring”
on page 77, then continue with step 8.
Location
Detector
Conduit Seal Within
Group B
Locations
All XP detectors
2 inches for all environments
Group C and
D Locations
Catalytic LEL (CSA)
2 inches for all environments
Catalytic LEL (UL)
18 inches for all environments
CO and H
2
S XP
2 inches for all environments
IR non-replaceable XP
18 inches for all environments
IR replaceable XP
18 inches for environments (do not install detector
in environments with acetic acid)
O
2
XP
www.
.com
1.800.561.8187
