But by post #37 it was fairly clear!
Max.

But who has time to read the whole thing when they have the answer?

 

But who has time to read the whole thing when they have the answer?

The original post was pertaining to switch's (not complaining though! I have learn't heaps! ).I have since decided that I would like "No Voltage Release" switch's ...................
I need assistance in choosing switch's please.For example one of the motors I have is a reversible CSCR single-phase 240 vac motor
Type:

GMYL90L2-2
Power: 3KW/4HP
Speed: 2 Pole (2800rpm)
Maximum amperage draws: 18.2Amp ...........I have been on ebay,mouser and others searching for an AC 20 amp switch.My understanding is I need one that has rated current (Ie (AC-3)) of 20 amps, is capable of 3kw induction motors, a rated voltage(Ue) of at least 240v an Ith of 20 amps at 40 degrees C (for my area) and a rated insulation voltage (UI) of at least 250 volts.From most searches I have found that most rate their switch's by the Ith value only,this to me seems to be an false capacity for the switch's full load draw.Am I totally wrong in my understanding of the above values? What I would like is an Estop switch and a push button red/green on/off switch with led's.Many thanks for taking the time to read

 

What I have found out is most rate their switch's by the "Ith: value for example I purchaced some switch's on eBay that stated they were 10 amp,however that was the Ith rating.The actual Amp rating was only 3 amp,so these have insufficient contacts .So I think what I really need to find for motors are switch's that have a rating via the Utilization Category of AC-3 (Squirrel-Cage Motors: starting, switches off motors during running time) and/or AC- 23 ( Switching of motor loads or other highly inductive loads).The motors I have are 4 x single phase 2.2kw the heaviest draw of these is almost 19 amps so I presume I will need switch's rated for at least 20 amps.The other motor I have is a 3 phase it draws just under 5 amps this is the motor that will use the Vfd to run it on 240 vac single phase.I have so far been unable to source any NVR switch's of sufficient amp capacity ....................................................... https://en.wikipedia.org/wiki/Utilization_categories

 

What would work best for your application, since I think what you mean by a no voltage release, is for the motor to have the power controlled by a latching circuit, so that if the power fails for even a second the system switches the motor power off until you deliberately switch it back on. That is a very good idea and mandatory in most industrial applications. For your application the least expensive part would be an air conditioning compressor contactor, probably one rated for a 220 volt 4 or 5 horsepower compressor. Many of those contactors have three poles, while some only have 2 poles switched. The best part is that you have double-break contacts, and on a 3-pole device you can use that third pole for the latching function. If the power is off long enough for the contactor to release then it will not start back up when the power returns, until you push the start button. AND, if the contactor coil is a 24 volt type, adding emergency stop switches is a lot less complicated.

 

What would work best for your application, since I think what you mean by a no voltage release, is for the motor to have the power controlled by a latching circuit, so that if the power fails for even a second the system switches the motor power off until you deliberately switch it back on. That is a very good idea and mandatory in most industrial applications. For your application the least expensive part would be an air conditioning compressor contactor, probably one rated for a 220 volt 4 or 5 horsepower compressor. Many of those contactors have three poles, while some only have 2 poles switched. The best part is that you have double-break contacts, and on a 3-pole device you can use that third pole for the latching function. If the power is off long enough for the contactor to release then it will not start back up when the power returns, until you push the start button. AND, if the contactor coil is a 24 volt type, adding emergency stop switches is a lot less complicated.

The closest I could find is this unit ,however it is only 15amp but will be fine for 3 of the motors ,not sure if I can also use this one with the 3 phase motor and VFD ? If you look at the pic it states AC-3 250V 15Amp ................ https://www.ebay.com.au/itm/AC250V-...e=STRK:MEBIDX:IT&_trksid=p2060353.m1438.l2649

 

The contactor you may want to look at is a Definite purpose contactor. Although these are designed mainly for applications that switch frequently such as heating, air conditioning, refrigeration, data processing, and food service equipment.
If you wire a contactor up with a typical start circuit it is fail safe, IOW you should not need a NVR switch.
Contactors as you show either have a 4th contact or an auxiliary contact for use as a retaining contact.
Max.

 

The closest I could find is this unit ,however it is only 15amp but will be fine for 3 of the motors ,not sure if I can also use this one with the 3 phase motor and VFD ? If you look at the pic it states AC-3 250V 15Amp ................ https://www.ebay.com.au/itm/AC250V-15A-NVR-Cut-Off-Emergency-Stop-Electrical-Saftey-Switch-DZ-6-2-Industrial/254064482975?ssPageName=STRK:MEBIDX:IT&_trksid=p2060353.m1438.l2649

That switch looks good, my only concern is the Faston terminals. I don't trust crimp-on connections in many applications because they are not always perfect, and thus subject to getting quite hot. There are other switches of similar appearance available, at least they were available, I used some of them that had a 30 amp rating. That would provide an adequate margin for most motor applications.
The brand name was Carlos Garvasi, or something like that. That is to say that right now I can't recall the second word of the name. But they make a lot of electrical items. 4AM and my mind is not at 100% yet.

 

That switch looks good, my only concern is the Faston terminals. I don't trust crimp-on connections in many applications because they are not always perfect, and thus subject to getting quite hot. There are other switches of similar appearance available, at least they were available, I used some of them that had a 30 amp rating. That would provide an adequate margin for most motor applications.
The brand name was Carlos Mar??. That is to say tghat right now I can't recall the second word of the name. But they make a lot of electrical items. 4AM and my mind is not at 100% yet.

McMaster Car ?https://www.mcmaster.com/

 

McMaster Car ?https://www.mcmaster.com/

The panel mount ones are similar to what I was thinking about. But elsewhere can be less expensive. Try Automation Direct. Theyt are the least expensive that is any good.

 

I have just started looking at Thermal Protection Overload Relay's do they all have common attachments to connect to the Contactor ? The one in the link below has an adjustable range of 12.5-20 Amps and that will suit all the motors except the 3 phase https://www.ebay.com.au/itm/A-JRS2-...746652&hash=item3aed5365e7:g:wYsAAOSwtZZbc9Yf ....................... These are contactors I have coming https://www.ebay.com.au/itm/2X-AC-C...e=STRK:MEBIDX:IT&_trksid=p2060353.m2749.l2649

 

Those DIN style contactors are either Telemecanique (Schneider) or a knock-off, the former have O/L's which attach to the bottom of the contactor and are adjustable for the range of the contactor.
They usually have one or two interlock terminals N.C. and often a N.O. as well, these are typically used to drop the contactor coil circuit out in the event of an O/L.
Incidentally most contactors have a H.P. rating on them as well as AC current.
https://www.widespreadsales.com/Products/Motor-Control-Telemecanique/LR2D1322
Max.

 

Those DIN style contactors are either Telemecanique (Schneider) or a knock-off, the former have O/L's which attach to the bottom of the contactor and are adjustable for the range of the contactor.
They usually have one or two interlock terminals N.C. and often a N.O. as well, these are typically used to drop the contactor coil circuit out in the event of an O/L.
Incidentally most contactors have a H.P. rating on them as well as AC current.
https://www.widespreadsales.com/Products/Motor-Control-Telemecanique/LR2D1322
Max.

Same one here I think Max ? https://www.ebay.com.au/itm/ONE-NEW...m2810ed8f29:g:negAAOSwNSxVcrd~&frcectupt=true

 

Again it looks like a Telemecanique knock off.
Hence the DIN EU style.
Telemecanique is/was a French Co, that made all kinds of electrical control products, they were eventually taken over by Group Schneider and many of the lines were dropped, they are now appearing in products from China with the original part No's on them.
I used them back then extensively.
Max.

 

Again it looks like a Telemecanique knock off.
Telemecanique is/was a French Co, that made all kinds of electrical control products, they were eventually taken over by Group Schneider and many of the lines were dropped, they are now appearing in products from China with the original part No's on them.
I used them back then extensively.
Max.

A couple of my motors are 13.7 amps would you know the model number for these?

 

Perhaps this unit LRD21C Thermal Overload Relay 12-18A ... LRD21https://www.ebay.com.au/itm/1PCS-Schneider-LRD21C-Thermal-Overload-Relay-12-18A-New/372429198251?epid=4002440630&hash=item56b68293ab:g:Wg4AAOSwwJ5bkpGK&frcectupt=true

 

Normally the O/L rating for a motor is x1.5 the maximum running current. Or FLA.
What is the HP, RPM of the motors again, 1ph?
Max.

 

Normally the O/L rating for a motor is x1.5 the maximum running current. Or FLA.
What is the HP, RPM of the motors again, 1ph?
Max.

2.2kw (3hp) 2800rpm 13.8amps 1ph x 4 , 3.7kw (5hp) 2800rpm 18.6amps 1ph x 1 , 2.2 kw (3hp) 2850rpm 4.8amps 3ph x 1

 

The LR2D series don't show up in the old catalogues I have, they show LR2D1522, LR2D3553 and LR2D1521 for those motors.
For use with the LC1D series of contactors.
I believe Schneider have a sizing chart on one of their web sites.
Max.

 

The original post was pertaining to switch's

My comment wasn't meant for you. It was meant for mrbill. He has a bad (in my opinion) history of reading the first and a few of the last posts in a thread and making comments that don't pertain to what the post has evolved into.

 

My comment wasn't meant for you. It was meant for mrbill. He has a bad (in my opinion) history of reading the first and a few of the last posts in a thread and making comments that don't pertain to what the post has evolved into.

I do need to work on that flaw, no question about that. Of course the other thing is that often some threads wander so far that the string of comments is not at all related to the original question. AND, when I respond to a post that is the last one on a page and have not yet scrolled down to realize that there is another whole page with an additional 18 posts that is also a cause of what you see on occasion. I sometimes reply to a post in the string but my response appears after an additional 15 or 20 posts. Sorry about that!!