Wiring - MSA SMC 5100-02-IT Operating Manual

3 Installation
After optimum locations are determined based on the above recommendations, consideration should be given to placing
the sensor modules in locations which are accessible for calibration service. Slight adjustments to the location of the
sensor module may have little impact on effectiveness but major effect on accessibility.
• Modules should be placed close to the potential source of gas.
• Modules should be placed in areas accessible for calibration.
• Sensors should be pointed down and the conduit should include an inverse trap to reduce moisture (condensation)
from accumulating in the electronics enclosure.
• The model 5311-02 rain shield can be used for remote calibration gas delivery. 1/4" OD tube fitting is provided for
convenient access.
3.3

Wiring

WARNING!
Additional precautions must be taken where the installation is near any sources of electromagnetic or radio frequency
interference. Precautions include:
Avoid running sensor module cable close to high power cables, radio transmission lines, or cables subject to pulses of high
current.
Avoid running cables near large electric motors or generators.
When the sensor module is to be operated in analog (4-20mA output) mode shielded cable is required.
When shielding is used, it is recommended that shields be grounded at the controller and nowhere else.
All splices must be via either a termination hardware system or soldered. Improperly spliced cable can result in corrosion,
resistance changes and system errors. The use of wire nuts and crimp-on connectors is unacceptable.
Relays are not to be used for safety critical functions.
Installation and wiring must be in accordance with the National Electrical Code. Voltage AC conductors are not to be run in
the same conduit as voltage DC conductors.
Failure to follow these warnings can result in serious personal injury or death.
12 SMC 5100-02-IT Gas Sensor US