Another reason thread starters should ask the real question from the first post.

 

The contactors I ordered have just arrived (CJX2-18) and the AC3 Ie at 220v is 18 amps the largest motor (1ph 3kw 4hp) I have has a maximum draw of 18.2 amps .I suppose 0.2 of an amp under will cause it to trip ?

 

The contactors I ordered have just arrived (CJX2-18) and the AC3 Ie at 220v is 18 amps the largest motor (1ph 3kw 4hp) I have has a maximum draw of 18.2 amps .I suppose 0.2 of an amp under will cause it to trip ?

The current rating for Contactors relates to the rating of the contacts relative to contact life. Motor starters include the overload sensors which may or not trigger on such a slight overload. And the 18.2 amps is full load current, and so unless you are running the motor at full load the draw should not be that much. So did you just get a contactor, or is it a motor starter, the difference being the overload sensors?

 

The current rating for Contactors relates to the rating of the contacts relative to contact life. Motor starters include the overload sensors which may or not trigger on such a slight overload. And the 18.2 amps is full load current, and so unless you are running the motor at full load the draw should not be that much. So did you just get a contactor, or is it a motor starter, the difference being the overload sensors?

To be honest I don't know.I have never dealt with this type of electrical.Most of my stuff has been basic DC stuff, house hold wiring,thermostats,actuators etc.What to purchase is all a bit over my head but I am learning I purchased 4 x CJX2-1810 contactors.I have since found that they are the same as Telemecanique, LC1-D .At the moment I am looking for thermal overload relays and have JUST found out that JRS1,LRD21 ,LRD22C,JRA and JRS2 "should" all fit the CJX2 contactors. Next I will be looking for Motor Protection Switch Breaker's (see link below) and some circuit breakers ............ https://www.ebay.com.au/itm/Motor-P...e=STRK:MEBIDX:IT&_trksid=p2060353.m1438.l2649

 

At the moment I am looking for thermal overload relays and have JUST found out that JRS1,LRD21 ,LRD22C,JRA and JRS2 "should" all fit the CJX2 contactors. Next I will be looking for Motor Protection Switch Breaker's (see link below) and some circuit breakers

Why all of those things? They are all different names for something that does the same thing. Most of the Telemanique/Schneider type contactors use the type you linked to, not a real overload heater like the older Allen Bradley style contactors.

 

Why all of those things? They are all different names for something that does the same thing. Most of the Telemanique/Schneider type contactors use the type you linked to, not a real overload heater like the older Allen Bradley style contactors.

They are all different names for something that does the same thing................Really I didn't know that buggered if if I know what I need

 

 

Not being right there and seeing what your doing, this thread has gone many places. But from memory your using a contactor and a motor. You have both, so all you need is the thing in your last link. It goes between the contactor and motor, and will shut down the contactor if the motor overloads. You do need the correct for the feed wire size circuit breaker in the main panel though.

Here is the best free one I found, though it is for 3phase -

you posted while I was looking. Something very unsettling to me while I was looking for this. A new site has gobbled up all of the good diagrams and want you to join their site to see them.

 

A big mistake in those wiring methods, do NOT use the old and outdated method of placing the O/L in the neutral line, this originally came about when wiring individual motor control units and saved on a conductor when wiring, but although you might see it in many modern machine drawings it is now considered a No-No.
IOW, you should never switch a grounded neutral line, the O.L should be wired in series with the retaining circuit. P.B.'s etc.
IEC60439/60947 applicable in Europe requires wiring the overload on the live side of the coil.
The current O/L's are electronic as opposed to the old AB etc, style which were heater resistors.
The other thing you may want to adopt in the future is 24vdc coils for the contactors, especially if you have 24v for the control circuits.
Max.

 

Incidentally this is the recommended way to wire a 1ph motor with a 3ph contactor and O/L's.
Max.

 

The specs for the contactor calls for a RT16 Square Pipe Fuse with arc suppressing media.I don't like the look of these and would like to use a RO15 10x38mm these with the holder look to me to be a far safer option.Can anyone see a problem with using these? Or a suggestion for something better Also would these go before the contactor? and to work out the correct size would be the FLA + any other amps used in switch's led's and contactor? Many thanks for reading

 

In a motor circuit the fuses are intended to protect the system in case of a short circuit, while the overload system is to protect the motor. So the fuses should be at the start of the chain, if there is a separate disconnect switch powering the whole arrangement. BUT if there is a disconnect switch just for the motor drive part, then the fuses should immediately follow that switch. The reason is that then the circuit can be switched off while the fuses are replaced. That is the arrangement that you will find in packaged fused-disconnect motor starters.

 

In a motor circuit the fuses are intended to protect the system in case of a short circuit, while the overload system is to protect the motor. So the fuses should be at the start of the chain, if there is a separate disconnect switch powering the whole arrangement. BUT if there is a disconnect switch just for the motor drive part, then the fuses should immediately follow that switch. The reason is that then the circuit can be switched off while the fuses are replaced. That is the arrangement that you will find in packaged fused-disconnect motor starters.

The supply will be from a power point and lead to a box housing the contactor,thermal relay and whatever else is needed from there to on/off switches

 

The supply will be from a power point and lead to a box housing the contactor,thermal relay and whatever else is needed from there to on/off switches

What exactly are you calling a "power point'?

Not to be cruel, but this whole thing is looking more and more like one of those questions that are, "if you have to ask, maybe you shouldn't be doing it".

 

What exactly are you calling a "power point'?

Not to be cruel, but this whole thing is looking more and more like one of those questions that are, "if you have to ask, maybe you shouldn't be doing it".

 

What exactly are you calling a "power point'?

Not to be cruel, but this whole thing is looking more and more like one of those questions that are, "if you have to ask, maybe you shouldn't be doing it".

 

What exactly are you calling a "power point'?

Not to be cruel, but this whole thing is looking more and more like one of those questions that are, "if you have to ask, maybe you shouldn't be doing it".

I have a few different ones laying around

 

I had a student from "India" pose that question to me too. He was looking for a "power point" which meant he was looking for an electrical outlet.

Another guy said he lived by a "Fore ist' . That was a forrest which in our parts are small wooded areas we call woods. His accent was on the second syllable which made it totally not understandable.

 

I had a student from "India" pose that question to me too. He was looking for a "power point" which meant he was looking for an electrical outlet.

Another guy said he lived by a "Fore ist' . That was a forrest which in our parts are small wooded areas we call woods. His accent was on the second syllable which made it totally not understandable.

In Australia the sparky term is "gpo" General power outlet.The most common term here is power point,basically 2.5mm2 wire coming from the meter leading to a 10amp gpo Edit I am still building the shed 5m x 3.5m pretty small but the biggest allowed by council.I have run a 6mm2 twin and earth from the meter box to a sub panel,most of the power points will be on 2.5mm2 wire but some for the heavier drawing equipment will be on 4mm2. An electrician friend will come and check my work and do the main connection