Sensor: Requirements for Installation in Hazardous Locations

Important Safety Instructions

Compliance with ATEX and HAZLOC safety standards is required when installing wireless Watchman Air sensors in a hazardous rated location. These standards specify that the sensor body must have an electrical resistance to earth ground of less than 1 GigaOhm. This requirement helps to ensure that a static charge does not accumulate on the sensor body, which could then serve as an ignition source. The below attached procedure demonstrates how to verify that an installed sensor meets this requirement.


Hardware Requirements

The following components are required to verify compliance with safety standards:

  • 1 Gigaohm verification resistor
    Note: This procedure uses a 1G Ohm, 5 Watt, 1% Tolerance, Axial Lead, High voltage glass glazed wire-wound resistor.

Additional Installation Notes:

The ‘machine ground reference point’ may be quite far away from where the sensor is installed. Meaning, the test leads on the instrument may not reach between that reference point and the body of the sensor.  In this case it is acceptable to use a pin-point probe tip and firmly press it to a bare metal surface of the machine.  An example could be area where the machine's paint was removed under the area of the sensor, exposing bare metal and using a section of that area that does not have adhesive on it could be acceptable.

Download the procedure below:

Was this article helpful?
1 out of 1 found this helpful
Have more questions? Submit a request


Powered by Zendesk