I personally don't see any down side to having the 2 parts used. It has a backup battery in the C/gem so it keeps the timing perfect!!
All you need to fit it is a X point and a small flat screwdriver, a spade connector to connect to the relay in the controller and a pair of wire cutters to cut and strip the electrifical string...
I would not contemplate switching the pump direct from the controller as the start current for something like a 1.5 hp pump would be too much for the relay in the controller. As I said I have ours switching a contactor so the only load is the contactor coil.
Where abouts in France are you Ty?
Most of the pool systems in Australia are run that way - Using the Chemigem as the controller of the pump as well as the Chlor/pH balance as its capabilities are superior to most Coffre Electric Clocks.
However it has been the habit of most pool installations in France to use the Coffre Electric to do this job, so we normally don't interfere with that as in your case Tygwenn. But in dire circumstances such as yours John there is no need to replace the Clock when its jiggered when there is a excellent timer controller already on the wall. You will have noticed that its easier to select the times for the pump to run using the nice big button then those annoying little peg affairs on the clock.
Anyway, thanks for the posting and glad that you have got a result.
Andrew
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