[SOLVED] Contactor CA7-30 (Sprecher + Schuh brand) have 3 terminals coil ???

[i200yrs]

Hello All...I got a faulty contactor CA7-30 (Sprecher + Schuh brand). I want to replace it but i found difficulty in searching for replacement because its contactor coil have 3 terminals....it has A1, A2, and 3rd coil terminal....Looking for replacement, all contactors I found online have 2 coil terminals only A1 and A2. Please someone enlightens me...please see image....thanks

 

[KlausST]

HI,

"CA7-30" is just a family name.
Please give the full part name or ordering number.

your photo.. isn´t very detailed, especially on the coil connections. Your "1", "2" and "3" is not according datasheet, thus it makes it difficult to refer to the datasheet.
I assume on the contactor every terminal has dedicated name.

Klaus

 

[betwixt]

Data sheet Page A64 shows the coil arrangement. If you have two incoming power wires and one motor you can probably replace it with a more standard contactor.

Brian.

 

[i200yrs]

Hello betwixt...good day...can you share the link of data sheet..I found some data sheet but can't find A64 page "(
thanks..

- - - Updated - - -

Good day mr KlausST, have dismantled the contactor down to the coil...see image below for the drawing....and also the 3rd coil terminal goes somewhere in the pcb of the unit...so this might be important..thanks

 

[i200yrs]

Data sheet Page A64 shows the coil arrangement. If you have two incoming power wires and one motor you can probably replace it with a more standard contactor.

Brian.

No motor is connected with this contactor...its installed for the 3phase AC input on high power dc power supply.

 

[Easy peasy]

..........

 

[FvM]

Simply typing in CA7-30 at Google gives you various manufacturer documents, some of it are listing coil options.

There's a "Two Winding DC Coils (CA7Y/D)" option, exclusively used for large DC driven contactors starting with CA7-60 and optionally available for smaller types.

The full type name of the "two coil" contactor is CA7-30Y-xxx and the device is probably still available.

Replacing the contactor with a different brand will involve changed parameters in any way, you might consider using a standard 24V DC contactor.

 

[KlausST]

Hi,

regarding post#5:
"3rd Terminal": does it have any "name" or description printet on the contactor? Was this "3rd terminal" used in your device?
Can you say how the coil was connected in your device?

From your resistance readings the order of connections should be:
A1 -- A2 -- 3rd Term.

100 (or 103) Ohms cause 5.7W of heat when connected to 24V
A2 - 3rd Term. --> Will never be connected to 24V, it causes too high current, too much heat.

Klaus

 

[FvM]

Power consumption of the "pick-up" winding is actually specified as 200 W. It's only operated for a few 10 ms.

 

[KlausST]

Hi,

OK this meets the 200W at 3 Ohms...

I still think that there is a complete part number printed on the contactor.
With this number we don´t need to waste more time to guess.

Klaus

 

[FvM]

Looking at the recent CA7 selection guide http://www.sprecherschuh.com/ecatalog/get/A/CA7_Contactors.pdf, it seems like the standard 24DC coil option is "electronic coil". Other types are probably not stocked. I would consider to change the circuit for this contactor type.

- - - Updated - - -

Reviewing the complete technical data from the Sprecher+Schuh website reveals that the CA7-30Y two windings DC coil option has been apparently cancelled, the below posted coil data are from an outdated document.

I would neither expect suitable replacement types from other vendors.

 

[i200yrs]

hello...thanks for continuous support...now step by step i did understand these 3 terminals coil...so let say i cant get the replacement and do have 2 terminals coils, can i add a resistor 3 ohms to as a replacement for 3rd terminal? Please see image for illustration. And also added the full data of contactor...thanks

 

[FvM]

You'll notice that the coil specification isn't included in the shown type plate, neither coil voltage nor two windings option.

I don't see a purpose for the 3 ohm resistor. The interesting question is if the "main" driver can supply the increased pick-up current demand of an electronic 24V coil. This can't be decided without analyzing the driver circuit.

 

[i200yrs]

Hello all...have tried to sketch the driver circuit but am kind of lost a long the way...by the way, there's a coil voltage rating on the contactor...so let say i will test the contactor by connecting the A1 and A2 to 24Vdc power supply (A1 positive and A2 negative) and 3rd terminal no connection. It should latch the contacts right?

 

[i200yrs]

Hello all...I got some info from manufacturer that this relay should be power up with at least 200W 24Vdc and you can't convert to standard contactor....thanks for all the replies and sharing...have to close this topic...have a great day!