Antique automatic transfer switch? 1920s

[Ricko1980]

Hi All,

A partner of mine saw a de-commissioned automatic transfer switch a while back, and now I'm trying to find more info online, but I can't seem to locate a picture or brand via Google. It was an all-electric house from the 20s that got built in the brief period when they didn't allow gas in the Berkeley hills after the 1921 fire. The transfer switch was designed to automatically latch so that when the range was on, the resistance heating system was no longer connected.

I'm looking for a picture of this kind of historic device, or a brand name, and/or any info on how long they were legal, and to know if other folks have seen similar ones out there from that long ago.

Weird question, I know, but it's caught my curiosity.

Ricko

 

[GoldDigger]

Are you talking about an actual transfer switch between normal and backup power, with some additional features for load control? Or are you talking about a pure load shedding device to be used even while on POCO power?

 

[Ricko1980]

A load shedding device for use while using power from the grid. My guess is there was no backup power there. It's essentially just an automatic 2-position switch, controlled by power draw on one of the legs. What sounded unusual to me was the "automatic" feature, whereby the range "locked out" the heating system when it started to draw current through the device.

 

[gadfly56]

A load shedding device for use while using power from the grid. My guess is there was no backup power there. It's essentially just an automatic 2-position switch, controlled by power draw on one of the legs. What sounded unusual to me was the "automatic" feature, whereby the range "locked out" the heating system when it started to draw current through the device.

Sounds like current through the branch to the range would drop out/pull in a contactor that would interrupt the branch(es) to the electric heat. I can't think how to do that, offhand. It's the end of the week and I'm low on sleep, so someone else will have to figure out how that happens.

 

[ATSman]

Hi All,

A partner of mine saw a de-commissioned automatic transfer switch a while back, and now I'm trying to find more info online, but I can't seem to locate a picture or brand via Google. It was an all-electric house from the 20s that got built in the brief period when they didn't allow gas in the Berkeley hills after the 1921 fire. The transfer switch was designed to automatically latch so that when the range was on, the resistance heating system was no longer connected.

I'm looking for a picture of this kind of historic device, or a brand name, and/or any info on how long they were legal, and to know if other folks have seen similar ones out there from that long ago.

Weird question, I know, but it's caught my curiosity.

Ricko

What you describe does not exactly fit into the definition of an ATS. Sounds more like a load shed/ load dump type of device that others have mentioned. It may be controlled by a current measuring device to determine when to lock-out a certain load to prevent overloading of the utility source. With no pics or nameplate/ mfg info you are not giving us much to go on but I'm sure we could design something if you have a specific application in mind.

 

[ATSman]

After I sent post #5, I realized I did not explain certain things. The logic that defines an ATS is such that once the voltage or frequency of the normal source moves out of the specified parameter range, it is designed to switch the load to the alternate source of power, if acceptable, whether a generator or other utility source. The device you describe is different in that the logic to determine when to lock out a specific load is based only on current. So this is the basic distinction between an "ATS" and the device you describe. Nevertheless it is an interesting discussion and would welcome any comments from others.