Low Voltage Relays


  #1  
Old 06-01-19, 02:01 PM
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Low Voltage Relays

Currently have the following installed in an older house (for controlling overhead room lights).

Bryant RR3B...originals

and

https://www.kyleswitchplates.com/low...-pass-seymour/

that someone has used to replace failed ones in the past.

Aside from being almost half the cost what is the difference between the 1070B (above) and

https://www.kyleswitchplates.com/ge-...-relay-switch/

All of the current relays are mounted in junction boxes and I can't tell if the RR7 can be also.

Could I use the RR7 as a direct replacement for some failed relays?
 
  #2  
Old 06-01-19, 05:12 PM
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Nothing different

As long as the line voltage connections (120v or higher) are inside the box there is nothing wrong with the RR7's or RR9's.
The 9's have an extra LV contact that I have used to know when the relay is made. The wires used to be yellow. if you do not need them so be it.
Depending on the age of the install the 24 V DC might be 24 VDC half wave. Check the rectifier to be sure. Do not cheap out on the recifiers the relays have a large inrush when they change state.
The 7's and 9's fit a standard 1/2 ko in a metal box. I say metal cause that is all I have ever used. Be careful of wire fill when installing the 7's or 9's.

I used to design lighting systems for school buildings to turn off the lights using a PLC. Lights go out people move towards the doors for closing. Works really well in Libraries.
 
  #3  
Old 06-01-19, 06:30 PM
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Depending on the age of the install the 24 V DC might be 24 VDC half wave. Check the rectifier to be sure
If I am just replacing a bad relay at the box, would I still need to do this, if so could you point me in a direction to accomplish this?

Be careful of wire fill when installing the 7's or 9's
The boxes that I will be working on I will be replacing with much larger metal boxes something along the lines of



Which are probably double in volume of the small boxes currently there.
 
  #4  
Old 06-10-19, 07:52 AM
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It would appear that no where that I can find has a wiring diagram for the Bryant system.
All I could find was this https://www.kyleswitchplates.com/ge-...mer-115v-277v/
It would seem that the industry has decided to do the conversion ac/dc inside the transformer, which is why it costs so much. It has been decades since I worked on these lighting systems. If it were my home it would be time to trace out all the LV wiring and identify each part and location for the future. Somewhere in your home there is a conversion location where the ac is changed to dc. It might not be in a easy location. Like in a box in the attic? The codes were pretty loose and fancy free back in the days when these were installed. No one was on the safety band wagon.
 
 

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