Noob Omron question

sbrugnoli · May 29, 2007

Hi,

I've been asked to design a system based on Omron CJ1M PLC. This is my first time doing that kind of job so I'm a bit confused. I have some doubts related to the power supply.

I need to feed the following modules (current consumption between "( )"):

- CJ1M-CPU11-ETN (0.58A, 5V)
- CJ1W-OC211 (0.096A, 24VDC)
- CJ1W-ID211 (0.08A, 5VDC)
- CJ1W-AD041-V1 (input signals (2): 1-10V, 4-20mA)
- CJ1W-DRM21 (0.29A, 5V)

So, as far as I understand I need two power supplies: one for the output relay module and one for the rest of the modules. So two CJ1W-PA202 modules would be right to power the system? Or am I just plain wrong?

Thanks in advance,

Sebastián.

scottmurphy · May 29, 2007

This follows standard hardware configuration, not just Omron.

The modules are powered from the PA202, which is part of the backplane.

The OC211 needs a seperate 24VDC supply to power the outputs that are switched by the module

svn · May 29, 2007

You need only one PA202 power supply. The PA202 generates both 5V and 24V internally and can provide upto 0.4A (and the OC211 card needs only 0.096A)

SVN

BobB · May 29, 2007

Use the PA202 to power the PLC internals. You really need a separate power supply for the outputs - talk to your Omron distributor.

scottmurphy · May 29, 2007

(and the OC211 card needs only 0.096A)

Does this include the output loads?

You really need a separate power supply for the outputs - talk to your Omron distributor.

This is the normal way to go, occasionally, on smaller systems, sometimes the onboard PSU is sufficient, but more than likely a
seperate supply is used.

sbrugnoli · May 31, 2007

Just for the record:

So just one power supply would be enough.

Thanks you all.

BobB · May 31, 2007

If you have a look in the CJ1 Operation Manual Appendix A - specifications of basic I/O units - the connections for relay output card type CJ1W-OC211 at the terminal connections it clearly shows an external power supply needs to be connected to drive the outputs. The reference you made above is to internal card consumption from the rack. How can the current draw for the card be so low on the 24VDC side if your load per relay is 1 amp - x 16 = 16 amps. The rack cannot supply that sort of power.

The CPU power supplies also do NOT have an extrnal connection to supply 24VDC to anything.

You even have to supply an external 24VDC power supply for the input cards as well.

Use an external power supply for your I/O!!!!!

scottmurphy · May 31, 2007

Not to gang up, but Bob is right.

Keep it simple.

Unless of course the poster has confused us.

would be right to power the system?

Maybe he was only asking about system configuration, and he/she
plans on using an external supply for his/her IO.

BobB · May 31, 2007

Scott, I get the impression that this person is under the impression that the relay outputs are powered from the rack power supply. This is not the case only the relay coils and LED indicators are powered from the rack - the relay contacts have to be powered from an external power supply.

svn · May 31, 2007

scottmurphy said:
Maybe he was only asking about system configuration, and he/she
plans on using an external supply for his/her IO.

From the original post I also thought so, thats why I said only one PA202 is required. He was asking whether two PA202s are required or one.

SVN

BobB · May 31, 2007

You cannot use 2 PA202s - only one can fit on the rack. They are designed to power the CPU/rack only - not outside stuff. They are noty a general power supply.Suggest he talks to his Omron distributor about a separate switchmode power supply to supply power for the I/O.

Noob Omron question

sbrugnoli

Member

scottmurphy

Member

svn

Member

BobB

Lifetime Supporting Member

scottmurphy

Member

sbrugnoli

Member

BobB

Lifetime Supporting Member

scottmurphy

Member

BobB

Lifetime Supporting Member

svn

Member

BobB

Lifetime Supporting Member

Similar Topics