Rating of Randall 103

[chrispvholmes]

Hi All,

I have an ancient Randall 103 which I am considering digging out to control TV/AV equipment.

I looked up the users guide online, and it?s rated at 6(2) A.

Anyone any thoughts as to what that means??

6 Amps at mains voltage would be plenty, 2 Amp might still be enough (40? LCD TV, sound bar, VCR, DVD and about half a dozen SMPS wall warts).

[Harry Bloomfield, Esq.]

[e-mail] submitted this idea :

If it has two outlets, one at 6amp, one at 2amps.

If there is one outlet it could meant 6amps resistive, 2amps inductive.

[chrispvholmes]

According to the book, you can use it for mains or ?low voltage?.

It maybe that one of the figures is for low voltage, but it would be nice if they explained!

[chrispvholmes]

Presumably the kind of load I?m talking of would be resistive??

[John Rumm]

I am assuming that is some kind of (mechanical?) time switch?

The maximum loads it can switch for resistive and inductive loads. So for electronic loads of any size you can count that as getting on for 6A of switching capacity.

[cpvh]

Thanks John,

That should be plenty. I'll just have to check the flex I wired it with and the plug fuse and maybe uprate them, and it should be good to go.

[tabbypurr]

+1, 6A resistive 2A inductive.

NT

[Andrew]

But a decent electronic timer will switch on and off as the waveform crosses zero surely ?. Mechanical ones might cause a momentary buzz, the ancient one that used to run my baxi bermuda back boiler, and now switches my hall light on and off does.

[tabbypurr]

I don't see why it would, and zero v does not eliminate inductive kickback.

NT

[Graham.]

In any case a Randall (Danfoss) 103 is an ancient mechanical time switch with a microswitch.

[Roger Hayter]

The zero of the voltage waveform does not happen at the same time as the zero of the current waveform, which is also a consequence of the inductance. So which do you choose?