Profilux II plus aquarium controller

[Matthias Gross]

Hi niloc,

bullit67 wrote he did NOT connect metal halide lamps to the socket which seems to make trouble.

To your case
The powerbars are even designed for 15A switching current. The relays are applicable for 250/16A.
The problem is the high so called inrush-current of inductive loads (here are the coils of your ballast inductive). At the moment of switching on the metal halide we have a current of up to 150A for some miliseconds! This current peak is to short to blow the fuse (otherwise your housefuse would also blow) but in some cases long enough to damage the relays.
This problem is always given with switching coils (eg ballasts for metal) and there are these solutions:
- use of an inrush current limiter
- spread the load to several sockets (maybe you connected some lamps to one socket?)
- use of an digital electronic ballast. (These electronic ballasts are standard in our metal halide lamps)

I know that other manufacturers of switchable powerbars have these problems too. Some solved it by the use of electronic switches. But these have the disadvantage that the can't shut off small loads (eg valves).
Others solved it using more sensitive fuses - here we have the problem that higher non inductive loads can't be driven either.

And could you please give me the exact watts for metal halide lamps you connected to the socket? Maybe you have the model/producer of your lamp/ballast?

Greetings

Matthias