The fault switches are hidden beneath a panel on the door of the control cubicle so they are not visible whilst the particular fault is being diagnosed. This allows the unit to be demonstrated in the classroom, which in the real world may not be possible. The cubicle is fitted with examples of the typical devices one may come across in the field, such as high and low pressure switches and a thermostat. The allows the lecturer to introduce 12 faults into a control circuit, which has been wired by the student. The Unit has a mimic diagram on the front panel, which simulates an actual compressor control circuit.
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