Boiler control circuit in heating plant - uses changeover to lower supply voltage to test each item of peripheral apparatus before plant is operated

摘要

The boiler control circuits in a heating plant normally supplied with 230 volts mains supply can be switched to a lower voltage for the systematic checking of the peripheral apparatus before the plant is set in operation. The switching device for the temporary voltage change can be a switch or a plug, and is only handled by the heating construction contractor. The testing of the peripheral apparatus uses liquid crystal displays for the results. ADVANTAGE - Simplest way to test for short circuits or incorrect wiring before full load operation.