I have 2 Carver amplifiers that draw too much power to plug into my switched AC outlets in the back of my Denon receiver and am looking for some kind of inexpensive solution that would sense when I power on/off my receiver and do the same by turning on/off power to my 2 amps.

Anyone have any suggestions? PLease e-maiol me at [email protected]

Thanks,

Claude H.

Claude, I will email you, but wanted to answer here, too. Sears has a Craftsman device in the tool dept. that is used for turning on a centralized shop vac system when a power tool is switched on. It has two receptacles for switched devices, and one for the controlling load.

I use mine for switching on my two Sunfire amps, a Stereo and a Cinema Grand, exactly the way you want to use yours. However, my preamp alone does not draw enough current to trip the device, so I use the 12V. trigger out to trip a power strip which I added a 12V. relay to, so my switched components and sub amps are switched. They add enough draw!

Larry
www.fineelectricco.com

Larry,

Thanks for the response.

Are you talking about this item? Approx $20. I called Sears on this and they were clu8less in Cincinatti about the function of this device.

[Link: sears.com]

I appreciate your help.

Claude H.

Forget about the above link, it worked once but not twice.

The craftsman autoswitch Sears p/n# 00924031000 is what I found. Is that the correct item?

Thanks,

Claude H.

Yes, Claude, that's the one.

Larry
www.fineelectricco.com

Thanks again,

Ordered it today.

Claude H.

That is simple to make. All you need is a power strip. a bosch 40 amp relay and a 12 volt 200 m.a power supply. The power supply has to be pluged in the switched outlet on you receiver.That will trigger your relay( pins 85 and 86)Pins 30 and 87 will now be your switch. Your power strip will switch on when your power supply is powered up.

Zinon, you left out a few small details, such as:

The relay and it's contact terminals must be housed in either a non-metallic or a grounded metal enclosure.

The terminals marked #85 and #86 should be insulated, as they are carrying line voltage (120v).

The aforementioned terminals must be wired in series with the black line wire in the power strip.

The best way to accomplish this is to use a box that has a receptacle for the power strip on it and a power cord sized large enough for your amps.


Here's what I did: I made my own switched power strip, using a strip I removed the manual switch from. I actually managed to fit two relays inside the power strip. Here's why I needed two:

My pre-pro has no switched 120v outlets, but has a 12v trigger output that is only capable of supplying 15ma, and the power relay I used for the current I wanted to switch needed more current, so I used a reed relay (12v coil) to switch the power relay (120v coil).

I plug in the miscellaneous items into this strip, such as my sub amps, wall warts, the rear-channel processor, etc. This strip is plugged into the socket on the Craftsman autoswitch, so turning on the pre-pro triggers the power strip, which in turn triggers the autoswitch.

One advantage of the cascaded switching arrangement is that not everything has to be on the same circuit.

Larry
www.fineelectricco.com

Radio Shack also used to make a "smart" power strip (I bought two in 1990). Don't know if they're still available. You plug a device such as your receiver into the "master" socket on the strip: Whenever you turn it on or off, the rest of the strip follows suit.

I can't give you a model number because it's in storage (I live in 220v land at the moment). Hope this helps.

-Bruce

Larry,
Thats a good idea using two relays.You can also use a switching transitor to trigger your relay.A lot of the newer projectors will have a screen trigger but with 15-20 m.a supply a switching transister in the is a must.Niles make a voltage activated ac outlet model # AC-3 and a current sensing switched outlet Model APC-2
both great units.
Zinon

I went with the reed relay so I wouldn't have to worry about the polarity. Plus, it can be used with any device that puts out 12v AC or DC, at either polarity, if I ever change pre-pros in the future

Larry