Those power saver adaptors

[Harry Bloomfield]

No, not those, the plug in adaptors which turn one, or maybe two items on/off, when the main item stops drawing power....

I'm thinking to power my two bench grinders as the 'main' item, to switch a light on over the grinding bench. Do the adaptors actually consume power, when in standby?

 

[hllns]

Barely anything but I've had two just give up over the years and they have about a 0.5 second switch-on lag.

 

[Harry Bloomfield]

I gave it a try, to power up a light, when either of - two bench grinders, or a bench drill was in use. It worked sometimes, sometimes not, often it switched back off, once the motors were up to speed. It worked fine, if any two items were switched on. Obviously not enough current draw to be reliable.

 

[SUNRAY]

What you require is a current rather than voltage operated relay.

I made my own using 24V AC relays, stripped the enamelled wire from the coil and replaced with some thick enough to take the motor current, adding enough turns to operate reliably.

EDIT: It occurs to me I may have posted about these before

Current sensing switch

Is there anything available that will turn an appliance on when another appliance starts? I would like to get a vacuum cleaner to start up when a bench saw is started. I'm sure it could be wired from the switch in the table saw but I would rather have something easier such as a device hat fits...

www.diynot.com

https://www.diynot.com/diy/attachments/upload_2021-3-21_0-34-16-png.227491/

 

[SUNRAY]

Or you could wire the light after the grinder switch.

 

[ericmark]

I have one issued to my dad by British Gas, it was designed to monitor the computer power being used, and turn on printer, modem, and other devices on/off with the PC, today with wireless printers and broad band and laptops using so little, it is really pointless, and I have been using it as normal extension lead for years. There is some button on the side that says mode, and a light which says status, and a 3.5 mm jack but I have never had the instructions for it.

 

[Harry Bloomfield]

What you require is a current rather than voltage operated relay.

I made my own using 24V AC relays, stripped the enamelled wire from the coil and replaced with some thick enough to take the motor current, adding enough turns to operate reliably.

Yep! Long ago, I did something similar....

I wanted to sense, and sound an alarm, when any of the PIR lights on a circuit was triggered. I simply would a few turns of the supply to the PIR's, around a transformer, rectified one of the outputs of the transformer, then connected Piezo sounder. It worked fine, for years.

Or you could wire the light after the grinder switch.

No, I don't want to delve into the machinery. I'll try something similar to the above, but feeding a relay, rather than a Piezo sounder.

 

[SUNRAY]

No, I don't want to delve into the machinery. I'll try something similar to the above, but feeding a relay, rather than a Piezo sounder.

Does your grinder have start/stop buttons and contactor?

In not; leave switched on and use an additional (external) switch.

 

[Harry Bloomfield]

Does your grinder have start/stop buttons and contactor?

In not; leave switched on and use an additional (external) switch.

Two bench grinders and a bench drill. The grinders have simple on/off switches, drill has strat/stop buttons. I was rather hoping to set it up, so that if any one of them was turned on, it would also switch the light on/off, over them. They are in a bit of a dark corner, and I would tend to leave the light on, perhaps for days, until I need to go back in there.

 

[SUNRAY]

Two bench grinders and a bench drill. The grinders have simple on/off switches, drill has strat/stop buttons. I was rather hoping to set it up, so that if any one of them was turned on, it would also switch the light on/off, over them. They are in a bit of a dark corner, and I would tend to leave the light on, perhaps for days, until I need to go back in there.

So nothing particularly powerful. Is my picture obvious?
If not the bit of enamelled wire coming out of the left of the clear plastic is a few turns of approx 1mm in place of the original thousands of very thin wire and exits the other side. I deliberately didn't try to use the original pins due to the high current of the pumps.
In my case I purchased those relay in trays of 50 so 'stock' item.
Cost naff all, free to run and simple.

Otherwise use a current clamp switch but most are solid state 'contacts' and limited to ELV.

 

[FrodoOne]

No, not those, the plug in adaptors which turn one, or maybe two items on/off, when the main item stops drawing power....

I'm thinking to power my two bench grinders as the 'main' item, to switch a light on over the grinding bench. Do the adaptors actually consume power, when in standby?

"Power Saver" adaptors seem to be a more "politically correct" name for that which has been called "Master/Slave" controls (PowerBoards etc.)
(Replacement names for "Master" include 'default', 'primary', 'controller', 'root', 'initiator', 'leader', 'director', 'manager'; and for "Slave": 'performer', 'worker', 'peripheral', 'responder', 'device', 'replica', 'satellite', and 'secondary'. - https://en.wikipedia.org/wiki/Master/slave_(technology) )

A "commercial module" which may suit your application is the Kemo M103N - Master/Slave switch 230 V/ AC
(https://www.kemo-electronic.de/en/T...3N-Master-Slave-switch-230-V-AC-400-V-AC-.php )

This "module" consumes <0.5W on standby - probably, for the Extra Low voltage supply for the "sensor" and the relay.


Then, there is https://www.ahoku.com.tw/en/product/Smart-Power-Management_CA-U609MS.html

 

[Harry Bloomfield]

This "module" consumes <0.5W on standby - probably, for the Extra Low voltage supply for the "sensor" and the relay.

Parasitic loads, is something I'm keen to avoid. I might use one of the machine once per month.

 

[FrodoOne]

All such "sensors" are likely to have some "standby" load.

It is my understanding that devices such as TVs, computers, microwave ovens etc are now required to have standby loads of less than 1 W.
This device seems to "comply" with that requirement.

How many devices do you have on "standby" around your premises?

 

[Harry Bloomfield]

All such "sensors" are likely to have some "standby" load.

The method I described above, involves no standby load at all.

It is my understanding that devices such as TVs, computers, microwave ovens etc are now required to have standby loads of less than 1 W.
This device seems to "comply" with that requirement.

No problem with that, if they are in fairly regular use, but this comes under the 'quite rare use', so difficult to justify.

How many devices do you have on "standby" around your premises?

Lots of slight loads, hence why I don't want to increase it. My partner brought with her an old TV, as a better size for the occasional use in the kitchen. I got around to checking it's standby consumption yesterday and was relieved to see it only consumed 0.4w - I was expecting it to be much more. .

 

[SUNRAY]

All such "sensors" are likely to have some "standby" load.

Just as Harry says: The method I describe with a current relay (modified AC relay) also has zero standby load and no additional in use load either.