Re: Electrical safety (was EVrelated(Siemens Electronic Brake))

[Lee Hart <leeahart@earthlink.net>]

Richard Furniss wrote:
> OK, I take the hint... so that means a isolation transformer...

That is what I would do. Isolation transformers are widely available,
and though expensive if bought new at full retail, are readily available
wholesale or surplus.

I am currently using a non-isolated Bonn charger in my EV, but it's
plugged into an isolation transformer, variac, and GFCI protected
outlet.

The Brigar transformers happen to be toroids, which are smaller and more
efficient that the usual cheaper rectangular transformers. But they have
funny voltages which may or may not suit you.

> Help me out here please, what am I looking for in an isolation
> transformer and where to find it. My car is 192v and I want to go
> higher, the controller will go up to 336v, I have a 14-50, 220v
> outlet, the charger will be variac, PFC-20 and maybe PFC-50...

The total VA determines how big a transformer you need. If you want 1500
VA or less (1500 watts), then it can be 120vac input. If you want more,
use 240vac input.

If you're charging a 192v pack with a variac, you obviously need 240vac
out from the transformer. The isolation transformer can have 120vac in,
240vac out (but you won't get over 2000 VA from a 120vac outlet).

With either a variac or a PFC20, you have great flexibility in the
actual output voltage of the transformer; it doesn't have to be a
standard 120vac or 240vac. This lets you use cheaper surplus
transformers that nobody else wants (like the Brigar toroids).

So I don't see the problem. Pick your input voltage and VA (power), and
get one (or more) transformers to do the job. You have lots of choices.
-- 
Lee A. Hart                Ring the bells that still can ring
814 8th Ave. N.            Forget your perfect offering
Sartell, MN 56377 USA      There is a crack in everything
leeahart_at_earthlink.net  That's how the light gets in - Leonard Cohen