Re: [OT] Diode equivalent needed - help!

["Alan Ainslie" <alan.ainslie@xxxxxxxxxxx>]

These are Zener diodes of 6W rating and 48V.

However, they are of a specialised class of device designed to absorb high
current surges very quickly as a PROTECTION mechanism rather than as a
voltage regulator.

The fact that it has cooked is a sure sign of something else adrift.

Try substituting a 48V zener temporarily, but if it does work, then you
need
to ensure that the correct class of device (Transorbs or Transient
Suppressors, unlikely from Maplin but easily available Farnell, RS
orothers)
for normal operation.

Chances are that this device is used as part of the regulator / protection
after voltage drop from AC mains via a series capacitor.  Therefore, before
doing anything else, look for a capacitor from Mains to the BAND end of the
device, and make sure that it is not short circuit.

If it is, then chances are that not only the Zener, but other devices on
the
low voltage side could well be damaged as well.  But worth replacing the
cap
and Zener to see: nothing lost in that case.  If the Zener did it's job
then
all will have been protected.

Alan Ainslie

----- Original Message -----
From: "Paul Gale" <groups@xxxxxxx>
To: <ukha_d@xxxxxxx>
Sent: Friday, September 23, 2005 5:46 PM
Subject: [ukha_d] [OT] Diode equivalent needed - help!


Hi all,

My bro has a problem with hi heating and found a burnt out diode in the
control panel. I need to find an equivalent to the following that can be
got
from Maplin on Sat.

BZW03C51 Zenner diode (glass bead type)

Can anyone help find a suitable alternative?

Of course, there could always be other problems on the PCB but it's worth
checking first :-)