On Fri, 22 Apr 2005 14:04:21 +0100, "Sparks" wrote:

"Peter Parry" wrote

Induction hobs use high frequency and high current in the induction
coils. The switching electronics produce a lot of RF interference
which needs to be filtered to stop it getting back into the mains
supply.

But this is happening with the hob on standby.

The filter is on the input - it is in circuit all the time unless the
hob isolator is open.

If I measure the current between its earth wire and Neutral, I am getting
about 2.9A

If you were really getting 2.9A flowing at 120V there is 350W being
dissipated somewhere in the hob all the time and you would feel the
heat generated without any problem at all.

The fact that the neutral to isolated chassis voltage is 120V
suggests the noise filter is serviceable and there is no marked
extraneous conduction path. The RCD is not always tripping
immediately which means there certainly isn't 2.9A or anything
remotely like it flowing all the time.

Can you connect the hob to a non-RCD circuit temporarily and measure
the current between the hob earth and mains earth?

What is the voltage between neutral and earth at the hob connector?

Connecting lots of things to a single 30mA RCD is a recipe for
nuisance tripping. You seem to have somewhat of an attachment to
RCD's so if you really want one connect the hob to a non-RCD circuit
and put a dedicated RCD on the hob alone.

So I will then get the 2.9A leaking to earth, 24/7 - Do I really want this?

Why would you have this? The hobs dedicated RCD would trip
immediately in this situation.



--
Peter Parry.
http://www.wpp.ltd.uk/