Jump to content

mains power question


IA76

Recommended Posts

Hi

 

A room is on the 2nd floor of a building and the 100v amp for that room is in the basement. The amp can't be moved. To power the amp on/off from the room is the only way to run a 3 core power cable from a switch in the room to the basement? The amp doesn't have a remote switch connection

 

 

 

Link to comment
Share on other sites

I'd leave the amp on and switch out the speakers. You'd need a load though, as most 100V amps can't run unloaded. The load could be a monitor speaker in the basement?

 

Surely that could result in music blaring out in the basement?!

Link to comment
Share on other sites

You'd need a load though, as most 100V amps can't run unloaded.

 

Can't they? I have never really thought about it but a lot have multiple switches for the 70/100V speaker outputs on them which can leave all the outputs off.

 

 

Link to comment
Share on other sites

Yes, a simple mains rated relay in a suitable enclosure. Mains in via an appropriate length of 1.5mm flex fitted with a 13 amp plug. Mains out via a 13 amp socket mounted on the enclosure. I would use a relay rated at the full 13 amps just in case someone re-uses the handy remote control device for a heater or something. Apply a warning notice to the socket and to the amplifier that states "WARNING, REMOTELY CONTROLLED, MAY BECOME LIVE WITHOUT WARNING"

 

Alternatively, if you do not mind slightly modifying the amplifier, you might be able to fit the relay internally. Suitable warning notice again required. Usual caveats about mains voltage.

 

Power the relay from a cheap plug top power supply of voltage to suit the relay coil, but preferably no less than 12 volts or voltage drop might be a problem.

 

The wire from the plug top PSU upstairs and the relay in the basement can be anything cheap, bell wire, speaker flex, phone cable etc.

 

 

 

 

 

Link to comment
Share on other sites

 

Alternatively, if you do not mind slightly modifying the amplifier, you might be able to fit the relay internally. Suitable warning notice again required. Usual caveats about mains voltage.

 

Power the relay from a cheap plug top power supply of voltage to suit the relay coil, but preferably no less than 12 volts or voltage drop might be a problem.

 

The wire from the plug top PSU upstairs and the relay in the basement can be anything cheap, bell wire, speaker flex, phone cable etc.

 

 

 

Indeed, if you're going to be that clever about it, take it these few final steps as well...

 

1. Use a DC power rail from the amp itself to operate the relay, so only a switch is required at the far end, no extra PSU.

 

2. Make the external connection on the amp using a break contact jack, so that unplugging the remote switch cable shorts out the remote switching and returns the amp to standard local switching.

 

 

 

Link to comment
Share on other sites

In these days of blame and litigation I would not consider internally modifying the internal mains wiring of the amp. If anything untoward were to happen with the system (even if nothing to do with your modification) you would be suspect no.1

 

A relay like this in a little box would be perfect

https://www.tlc-direct.co.uk/Products/SR504.html

 

I'm surprised nobody makes a plug-in 12v controlled relay with a socket outlet on it, but there only seem to be radio ones which probably wouldn't work reliably.

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.