300vac-2x22 transformer get hot?

[EmergencyDpt]

Hi.
I'm putting together the box for my AMP10 and I'm going to put the tranformer in its own vacuum formed holder. However this might retain some heat.
Does that thing get hot at all? I can use special plastic that is more heat resistant if it does. If not, the cheap stuff will work fine.
Thanks,

 

[Nuuk]

Do you mean encapsulating the transformer like this ?

 

[AndrewT]

many transformers are rated using maximum operating temperature as the limiting criteria.
These usually state the maximum ambient temperature, often between 40degC and 70degC. These usually take the core and/or insulation to somewhere around 130degC

If the temperature inside your plastic case (or any enclosure) reaches the specified limiting temperature, you must de-rate the transformer using the manufacturer's advice/data.

But, do you want your transformer to operate at temperatures anywhere near those limits?
I certainly don't.

 

[EmergencyDpt]

Hi Nuuk.
Thanks for your reply.
I don't think that those are examples of what I want to do.
I am using a thin thermoplastic and molding it around the trafo. Just to make a case for it to sit in nicely. Everyone needs a home.


Andrew, thanks for your reply.
Very informative. I see that you are telling me that the manufacturers rate the voltage for it's maximum temperature which is 130c. That's very hot. I will make sure my enclosure can withstand such a high temperature.

In answer to your question, no I don't want my tranformer to run hot. However I don't think I can control its operating temperature except to change the load it's running under. If someone else uses the equipment without understanding that it can get very hot, they may use it carelessly so I need to make sure everything holds together at high temperature.

Thanks both of you for your help.

 

[AndrewT]

......... maximum temperature which is 130c. That's very hot. I will make sure my enclosure can withstand such a high temperature.

In answer to your question, no I don't want my tranformer to run hot. However I don't think I can control its operating temperature

you are controlling the operating temperature of the transformer.
Putting the transformer inside an enclosure is forcing the operating temperature up, much higher than if the ambient can cool the outside of the device.

Be sensible, get as much cooling air to the uncased transformer as your vented amplifier casing can manage.

 

[Nuuk]

Andrew, wouldn't encapsulated transformers also risk over-heating then?

 

[AndrewT]

Andrew, wouldn't encapsulated transformers also risk over-heating then?

If the manufacturer has designed and tested them and specified them honestly then they should operate within their specification.

If we go and modify them then we face the consequences.
Be informed before making decisions.

 

[EmergencyDpt]

Thank you Andrew. Being informed is always good advice.

Nuuk I appreciate your input also.

I'll be sure to post pictures when it's done so you can see what I'm talking about.

Thanks,

 

[zoranaudio]

Hello!!!
If your transformer is toroid tyope and without any load on the tempereture must be under 50 deg C, in my cases just 5 deg plus ambient room temperature.
You must use a insulators on thecentral bolt or at the bottom of that case if is from metal!!!!!or you gonna make a "short circuit) wind via that metal case!!!!!!!!
Good luck

 

[EmergencyDpt]

Thanks Zaudio,
The case is wood and plastic...soaked in kerosene to keep it cool

 

[Nuuk]

The case is wood and plastic...soaked in kerosene to keep it cool

You can still afford kerosene!