British General Fortress 8-24V AC 8VA Bell Transformer Module (8707P)

Hi GreenDave, Based on your kWh charge suggestion (which a quick internet search seems to indicate is a possibly a little high). 45mA at 240V (nominally) is 10.8W, and this drops to 10.35W if you take a more average 230V. Still 10.8W, or 0.0108 x 28p = 0.3024p/h, x24h = 7.2576p/day, x365.25 = 2650.8384p or £26.51 (which drops to £25.40 at 230V). One other thing to bear in mind, the no-load readings for a transformer coil can (sometimes) be skewed an unpredictable amount by interactions between the actual transformer coil and the sensing coils in the meter, which if it happens almost invariably causes a `phantom' rise in the readings.

Hi BobBeer As long as the wattage of both door bells does not exceed the 8VA rating when connected to the circuit (8W), then you should be able to add both doorbells on this single Bell Transformer Hope this helps,should you require any further assitance please contact us directly on 01952 238128

Hi Wardy2, We do not have any specific technical details for other manufacturers' enclosures or devices, but we would expect that the vast majority of circuit protection devices are within an acceptable tolerance of being the same dimensions. We don't think you will have much luck trying to squeeze the transformer beneath the front cover though as it has a section which sticks out through the usual device slot just as much as our other devices (MCBs, RCBOs, RCDs etc.).

Humm, I’m not sure I like the ”official” response. A simple transformer as this will be will have the same non-load, as load-voltage. The product may not be quite right, so try between 16v and 24v to get 8 V. Or Your meter is not reading RMS correctly and it’s actually working fine, delivering 8VRMS, but being measured as 12V Peak to peak.