Albert hall, what were you thinking?? I am not really following you. I agree with 220 connected to the NC position, if I am running both 110/240 thru one cord, the coil would be energized if I applied 110v to energize the coil to trip the NO circuit, but when the 240v hits the coil if it is a 110v coil it will burn out would it not?

When 110V input power is applied the relay should operate to switch to 110V.
When 240V input power is applied the relay should NOT operate to leave set to 240V input so 240V would NOT be applied to the coil and so a 110V relay coil will never have 240V applied to it.
Therefore you need a circuit to only energise the relay coil when 110V is applied but not when 240V is applied.

 

When 110V input power is applied the relay should operate to switch to 110V.
When 240V input power is applied the relay should NOT operate to leave set to 240V input so 240V would NOT be applied to the coil and so a 110V relay coil will never have 240V applied to it.
Therefore you need a circuit to only energise the relay coil when 110V is applied but not when 240V is applied.

But the cord to the wall outlet will carry either 110v if connected to the us, and 240 if connected to a outlet in another country. there for if I connect the 110 to the coil and to the NO, it will power the coil no problem BUT, if I connect 240 it is now going to energize the coil and the NC tripping it to the 110v burning out the system. ONE cord 2 voltages.

 

When 110V input power is applied the relay should operate to switch to 110V.
When 240V input power is applied the relay should NOT operate to leave set to 240V input so 240V would NOT be applied to the coil and so a 110V relay coil will never have 240V applied to it.
Therefore you need a circuit to only energise the relay coil when 110V is applied but not when 240V is applied.

I am trying to avoid extra cords, i.e. one for 110, and one for 240. If I have read you correct, your setup would require 2 cords, one for 110v to the coil, to the NO to connect the 110v circuit, and one cord 240v to bypass the coil directly to the NC 240v

Correct me if I am wrong.

 

When 110V input power is applied the relay should operate to switch to 110V.
When 240V input power is applied the relay should NOT operate to leave set to 240V input so 240V would NOT be applied to the coil and so a 110V relay coil will never have 240V applied to it.
Therefore you need a circuit to only energise the relay coil when 110V is applied but not when 240V is applied.

Yes albert I need something that Isolates the 240 from the coil, to prevent burning of the coil, and prevent the coil from tripping to NO.

How do I build a circuit that energizes the coil on the 110v side, but leaves the 240v de energized. NC

 

How do I build a circuit that energizes the coil on the 110v side, but leaves the 240v de energized

To quote Shakespeare: "That is the question".
You need something to power the circuit - probably a transformer.
You need to measure the mains voltage - probably best by measuring the transformer voltage.
Then, after a delay to allow the voltage to stabilise, operate the voltage selection relay as appropriate and this relay is now best as a low voltage relay running from the new transformer.

 

If you think of your computer and most chargers for phones, they already do this automatically

Not really. They include a switch-mode power supply which works on a different principle and can accept an input of anything in the range 90-240VAC with no changeover.

 

I haven't thought this through fully, but couldn't you do what you want using a pair of single-pole relays plus a voltage-sensing/threshold circuit? Initially neither relay would be energised. Then the circuit would energise one or other relay as appropriate.

 

Not really. They include a switch-mode power supply which works on a different principle and can accept an input of anything in the range 90-240VAC with no changeover.

Alec do they have any out there with a 10-12.5 amp rating, I have not found any. ergo my asking

 

I haven't thought this through fully, but couldn't you do what you want using a pair of single-pole relays plus a voltage-sensing/threshold circuit? Initially neither relay would be energised. Then the circuit would energise one or other relay as appropriate.

Alec please send me a link on where to purchase a voltage sensing threshold circuit or if not can you tell me how to build one with a schematic and parts list

 

His concern seems to be that 220V will be momentarily applied to the 110V input during the delay of the relay switching (below).

My concern is that with the contacts closed in the 110v position, when I apply 240v to switch on the coil and close the contacts to the 240v position, that, that millisecond of 240 <<presumably AC 'mains'>> applied to the 110 contacts will burn out the components of this ac/dc inverter.

---Emphasis and <<text>> added---

Based upon his/her OP (quoted immediately above) and the assumption that "AC/DC inverter" was a typo (DC/AC inverter being my interpretation) it seemed @born2dive00 wished to implement some manner of 'transfer switch'...

But then:

Is there any way to do this with out relays like on a computer charger? but with 10A DC out?

--Emphasis Added--

--And--

View attachment 119471

My head hurts!

All of which is to say - Very pleased someone is able to follow this!

Best regards
HP

 

Alec please send me a link on where to purchase a voltage sensing threshold circuit or if not can you tell me how to build one with a schematic and parts list

Alec I have found this, would this work, and if so how do I modify it to trip the relay?

 

I have found this

Note that we are not allowed the discuss this type of power supply on here.

 

Note that we are not allowed the discuss this type of power supply on here.

@born2dive00

Hint: lead nodes 'L' & 'N' with the secondary of an isolation transformer

Best regards
HP

 

Alec I have found this, would this work, and if so how do I modify it to trip the relay?View attachment 119481

this is the website http://www.electroschematics.com/11922/mains-voltage-sensor/

 

---Emphasis and <<text>> added---

Based upon his/her OP (quoted immediately above) and the assumption that "AC/DC inverter" was a typo (DC/AC inverter being my interpretation) it seemed @born2dive00 wished to implement some manner of 'transfer switch'...

But then:


--Emphasis Added--

--And--




My head hurts!

All of which is to say - Very pleased someone is able to follow this!

Best regards
HP

Hello hypatas proto, take a look at reply 17 it has a schematic as to what I am trying to do

 

@born2dive00

Hint: lead nodes 'L' & 'N' with the secondary of an isolation transformer

Best regards
HP

Hypatias protégé, ???? I don't understand the hint, I can build things from a schematic, but I don't have the working experience on how to design them. can you please elaborate more

 

I think alec is on the right track with the voltage-sensing/threshold circuit but I do not know how to design one that will work for ac

 

Will this chip AVS10 help?:

http://educypedia.karadimov.info/library/3571.pdf

http://www.st.com/content/ccc/resou...df/jcr:content/translations/en.CD00000665.pdf

http://www.st.com/en/thyristors-scr-and-ac-switches/avs10cb.html

 

Alec I have found this, would this work, and if so how do I modify it to trip the relay?View attachment 119481

PUT A TRANSFORMER ON THE LIVE AND NEUTRAL, that way your post wont get deleted, as for the circuit you need to detect anything over 150V.

 

PUT A TRANSFORMER ON THE LIVE AND NEUTRAL, that way your post wont get deleted, as for the circuit you need to detect anything over 150V.

Dodgy dave, I don't think that putting a transformer on will work in this case, Correct me if I am wrong but that will emit Magnetic/RF interference without a faraday cage?? This power supply is going on my nephews " FPV base station" rc controls using 72.mhz, 433mhz, 1.3 ghz and 2.4ghz frequencies. any unfiltered system will cause interference wont it?

This is why I am trying to find out a very simple low rf interference solution