XM-18 Incubator Controller

XM18 is our standard controller with a long and positive service history as long as:

a) The controller is in fact our fitted original genuine one, not a cheap eBay imitation/copy

b) The On/Off set point for heat and humidity are spaced out, so the relays are not overworked, and

c) The mains power is between 220VAC and 240VAC, which in many areas is exceeded due to a concentration of private solar-energy “vendors” bidding up the daytime line voltage.

Before placing your order, if your controller is fairly new, check that the failure is not caused through “fatigue” from over-voltage.
Check your working voltage, and check again at midday on a sunny day.

To export its product, the equipment of private solar vendors must increase its voltage to a value higher than what is on the lines outside. Where there’s a cluster of rooftop solar, this automatic bidding can increase the midday voltage locally. In addition, it’s been reported that unscrupulous persons willfully escalate their “winning bids” to over 270 VAC.

You just need a cheap digital multimeter, set on 500 VAC.
In a house wall socket switched off, put the black probe in the earth slot and the red probe in the active slot.

It doesn’t matter if you put the red probe in the wrong slot first and get a null.
That would be the neutral. Switch off, change the red probe to the other slot, and switch on again.

See if the meter registers between 230 and 240 volts.
If it’s seriously out of spec, contact your energy provider and they are obliged to rectify it.

If they’re not able to, or if you yourself have solar, when you replace the controller, run it through an inexpensive voltage regulator/stabiliser costing about the same as the controller.

Over-voltage is damaging. Your new controller, as are all the incubator’s electrical components, is running continuously in a hot environment. The excess voltage is absorbed as heat inside the components and shortens service life.