The idea of adding that tape was in the PDF from Tyco when converting relay from AC to DC. Something about residual magnetism may not let it release properly.
I will see how it works without doing such.

"To negate the effects of residual magnetism, a small piece of mylar tape
may be stuck to the top of the AC relay core. This tape is extremely
durable, and should last for perhaps hundreds (if not thousands) of
operations. The tape should be .002” to .004” thickness."

How do you quote text?

 

How do you quote text?

QUOTE and /QUOTE with [] around each.
Max.

 

The idea of adding that tape was in the PDF from Tyco when converting relay from AC to DC. Something about residual magnetism may not let it release properly.
I will see how it works without doing such.

That's what I would tend to do, I can see it possibly with a small control relay, but a contactor style relay is heavier duty.
Max.

 

Usually their is a quote icon to make it easy.

Thanks

 

So

If the power drops under a big load, the relay buzzes. I suppose due to not enough magnetic strength being generated, also due to the shore power supply not all that great.

This part didn't throw up a huge red flag for a bigger problem elsewhere in his system for anyone else?

 

So
This part didn't throw up a huge red flag for a bigger problem elsewhere in his system for anyone else?

It is at a marina and sometimes the power volts will drop with heavy loads. I have seen it as low as 100 vac (last summer if I turned on microwave and had AC running) but not often. That caused relay to very loudly buzz.
Typically it is 120vac. Marina also has upgraded some electrical stuff tpast 2 months, An electrician came through changed plugs, a distribution box and tightened up wires. Like yesterday, power stayed at 120vac. I think it has to do with too many people and their wiring too small. I am on a 30 amp shore power circuit. The electricity is free, no monthly bill.

 

Happy to say, ALL power warts ran the relay well with a good solid click down if they rated 12v or higher. The linear warts all read a lot more than 12v. I have a switcher wart 15 v 1 amp I like. It's input is 100 to 120 vac, which I suppose means it maintains 15vdc output.
Will the linear warts work undervolted? How can I simulate a brown out for them?

A 12v car battery can not pull down the relay. Neither can one of my 12vdc car battery chargers. At rest it reads 11 vdc, but on a charging battery, it goes as high as 16v, which I dont know why they do that.

 

Corrected:
You really need something such as a Variac to test brown out conditions, I would expect the Switched versions to maintain down to at least -10%/-12%.
When you post in haste you make mistakes! The linear supplies will usually drop in proportion
to the applied AC.
Max.

 

This one works well so far.
I need to test with dropped voltage. I thought maybe using some nichrome heater wire and some sliding clips I could drop the AC volts to test more.
Linear supply says 12 v but when powering relay coil read 14.6v at 118vac.
This one actually feels cooler running that the 15v switcher wart.

I also have also a 15 v linear wart which I am testing. Connected to relay is 17.2v
I will let it run all day to see if it warms up too hot. If it seems ok, I will likely use the 15v linear as it will keep the volts higher if they dip. Dont want the relay to cut out.

An interesting good reason to use a wart, consider if mains power browns out. With a relay and wart, maybe could be set so not enough volts to close the relay which would protect your downstream electrics from a brownout condition. If power too low, turn on switch but you wont get power idea.

I also tried the nichrome wire, but had no effect on the supply voltage, likely due to not enough current to heat and get more resistance. Even 15 feet nichrome was not enough to drop the voltage.

 

I will likely use the 15v linear as it will keep the volts higher if they dip. Dont want the relay to cut out.

As per post#14, once the relay has pulled in it requires much less energy to retain it, usually quite a bit lower than the pull in level (Hysteresis).
Max.

 

Try one or more small incandescent bulb(s), such as a night-light in series with the AC mains to drop the voltage.

 

I let it run all morning using the linear 15 volt 400 milliamp wart. The volts are 17.3 vdc on the coil.
I covered relay with cardboard box to simulate an enclosure.
I measured the temp with the digital meter under the coil armature at 98*F and it never goes higher. That seems ok to me.

The lamp is sort of interesting, would it glow at a low level? Of course if the bulb fails, I loose all the AC power for the boat. that would be bad. Lose charger and fridge.