Criterion 6.1.5.5 Control Lines and Sensors

Criterion text:
All wires and connections, sensors, pneumatic lines, hydraulic lines or other means for transmitting sensor outputs to control devices shall be sufficiently protected from degradation or from introducing false signals as a result of environmental or system operating conditions. (Also see 6.1.5.4, 6.1.2.2, 6.2.2)

Comments:
This criterion deals primarily with transmission of sensor outputs - sensor wiring and sensor leads. Means must be taken to protect the wiring from degradation or from false signal interference.

The installer must follow the manufacturer's recommended (and SRCC approved) installation methods as well as accepted industry standards.

It must be stressed that the installer bears the responsibility at the site of ensuring that the control wiring is installed (and routed) in such a manner that prevents degradation and false signals.

Figure 1 illustrates how installers must use common sense to protect sensor wiring. Routing wiring adjacent to sharp edges that can cut into wire should be avoided.

Figure 1

In addition, installers must keep controller sensor wires away from direct contact with 220V lines. Sensor wiring should be kept well away from the 220V line to the water heater in Figure 2.

Figure 2

Loose, unsecured wiring (Figure 3) can be damaged and operationally compromised by being tripped over and disconnected.

Figure 3

Related UV protection and prevention from solar degradation of the sensor wiring is covered in Criterions 6.2.2 and 6.1.2.2.

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