Hi all

Recently fitted a Texecom Excel panel and noticed that the transformer has a
very audible hum!
Does this suggest weakness?
My previous panel (Pyronix Super) was silent.
Does the size of battery fitted have any relevance - I increased the battery
from 1.2Ah in the old panel to 7Ah in the new one.

TIA

Phil

After serious thinking TheScullster wrote :
Hi all

Recently fitted a Texecom Excel panel and noticed that the transformer has a
very audible hum!
Does this suggest weakness?

The hum could be either loose laminations on the transformer, or mains
hum noise coming from a speaker/sounder. You need to work out which of
the two first.


My previous panel (Pyronix Super) was silent.
Does the size of battery fitted have any relevance - I increased the battery
from 1.2Ah in the old panel to 7Ah in the new one.

If the battery was not fully charged when installed into the unit, then
it might be taking more current than usual to charge it up and thus
might be causing some of the hum.

--
Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.co.uk

i think you will find four screws holding the transformer. give them a
tweak

TheScullster wrote:

Hi all

Recently fitted a Texecom Excel panel and noticed that the transformer has a
very audible hum!
Does this suggest weakness?
My previous panel (Pyronix Super) was silent.
Does the size of battery fitted have any relevance - I increased the battery
from 1.2Ah in the old panel to 7Ah in the new one.

TIA

Phil

Hi
Another common cause is if the panel is not fitted to a flat surface or a
cable fouls it against the wall.
Try light pressure against each corner & see if the hum increases or goes.As
for battery IIR the Excell range will support a 7ah no problem if in doubt
try
www.text.com they are very helpful.

CJ

TheScullster wrote:
Hi all

Recently fitted a Texecom Excel panel and noticed that the transformer has a
very audible hum!
Does this suggest weakness?
My previous panel (Pyronix Super) was silent.
Does the size of battery fitted have any relevance - I increased the battery
from 1.2Ah in the old panel to 7Ah in the new one.

TIA

Phil

Hum is occasionally a problem with mains transformers.
1. Tke a hammer & cold chisel, and give the laminations a whack
on each side. This jams the lams together, stopping hum.
2. Mount the transformer on rubber washers and it'll be much
quieter.


NT

wrote


Hum is occasionally a problem with mains transformers.
1. Tke a hammer & cold chisel, and give the laminations a whack
on each side. This jams the lams together, stopping hum.
2. Mount the transformer on rubber washers and it'll be much
quieter.


Thanks to all.
Prefer the sound of tweaking the transformer screws rather than hitting the
thing with a hammer and chisel.
The panel is already mounted off the wall on flexible packers.

Phil

"TheScullster" wrote in message
. uk...

wrote


Hum is occasionally a problem with mains transformers.
1. Tke a hammer & cold chisel, and give the laminations a whack
on each side. This jams the lams together, stopping hum.
2. Mount the transformer on rubber washers and it'll be much
quieter.


Thanks to all.
Prefer the sound of tweaking the transformer screws rather than hitting
the thing with a hammer and chisel.
The panel is already mounted off the wall on flexible packers.

Doing that may make it worse.

TheScullster formulated on Friday :
Thanks to all.
Prefer the sound of tweaking the transformer screws rather than hitting the
thing with a hammer and chisel.
The panel is already mounted off the wall on flexible packers.

Rather than hitting the laminations with a hammer....

On these small transformers there is usually a soft metal strap
surrounding the laminations which is U shaped. Squeeze the sides of the
U, perhaps in a vice.

--
Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.co.uk

"cj" wrote in message ...
Hi
Another common cause is if the panel is not fitted to a flat surface or a
cable fouls it against the wall.
Try light pressure against each corner & see if the hum increases or
goes.As for battery IIR the Excell range will support a 7ah no problem if
in doubt try
www.text.com they are very helpful.

CJ



or even www.texe.com

Rgds

Steve

OOPS!!
sorry typo

CJ

Harry Bloomfield wrote:
TheScullster formulated on Friday :
Thanks to all.
Prefer the sound of tweaking the transformer screws rather than
hitting the thing with a hammer and chisel.
The panel is already mounted off the wall on flexible packers.

Rather than hitting the laminations with a hammer....

On these small transformers there is usually a soft metal strap
surrounding the laminations which is U shaped. Squeeze the sides of the
U, perhaps in a vice.

dribble epoxy resin into the transformer.

TheScullster wrote:
wrote

Hum is occasionally a problem with mains transformers.
1. Tke a hammer & cold chisel, and give the laminations a whack
on each side. This jams the lams together, stopping hum.
2. Mount the transformer on rubber washers and it'll be much
quieter.


Thanks to all.
Prefer the sound of tweaking the transformer screws rather than hitting the
thing with a hammer and chisel.
The panel is already mounted off the wall on flexible packers.

Phil

One of those will work for you, one wont. We dont know which
until you try them. Hammering lams is standard practice for
silencing noisy transformers. Obviously one removes the thing
from the kit first Pointed chisel required, not a flat edged one.


NT