Replacing PLC-5 with CLX - possible?

flyers · May 14, 2011

Hi guys,

Currently, we are working for a client to replace the existing PLC-5 system with CLX. There are 2 modules (1771-IT & 1771-DS) in the PLC-5 rack. Does anyone know what is the suitable module in CLX system that we can use?

For 1771-IT if not mistaken can be replace with 1756-PLS. The 1771-IT are connecting to a encoder controller module.

The description for 1771-DS is Input latching module (10-27VDC).

Thanks guys!

MichaelG · May 14, 2011

More Information Please

Depends on what it is connect to and what you need to achieve.

Please detail what both cards are connected to and what the code is doing with it.

A PLS is connected to a sin/cos Resolver, it can change an output in response to an input within 0.05 ms - No Resolver No PLS module needed

A M02AE Card connects to A Quad B Encoders giving you position Speed and acceleration of the encoder Plus 2 registration inputs that operate capture registration event at 20 us

Look more closely at 1756-IB16ISOE - This gives you a sequence of events which is closer to the DS card

Note: Almost any digital input card can be made to respond to a change of state of an input which can be captured with its event time (CST)

jdbrandt · May 14, 2011

flyers said:
Hi guys,

Currently, we are working for a client to replace the existing PLC-5 system with CLX. There are 2 modules (1771-IT & 1771-DS) in the PLC-5 rack. Does anyone know what is the suitable module in CLX system that we can use?

For 1771-IT if not mistaken can be replace with 1756-PLS. The 1771-IT are connecting to a encoder controller module.

The description for 1771-DS is Input latching module (10-27VDC).

Thanks guys!

Skip the nightmare, and use a Beckhoff BK9105 Ethernet/IP coupler and then just use the correct terminal module to do the work. I've just installed my first one, and after that experience, for-the-life-of-me, I just don't <<get>> why everybody wants to fit every problem into the Rockwell I/O module box.
Define the problem, and solve the problem with the right tools, regardless of the choice of processor.
IMHO, of course.

Ken Roach · May 15, 2011

You have to investigate how these modules are being used in *this* application.

Using a 1756 discrete input module in the local chassis with the controller, and using the Change-of-State trigger for an Event Task will allow you to cover virtually all applications of the 1771-IT fast input module.

The 1771-IT had an input delay time of 0.6 ms +/- .2 ms, while the 1756-IB16 module has an input delay time of 1 ms Off->On, and 2 ms On-Off. If your inputs are longer than 2 ms then you're great... if not, then you have to keep looking.

The 1771-DS had some boolean comparison features and some extremely fast input filters that no modern module has. An encoder module, a 1756-PLS module, some networked module from Beckhoff or AMCI or Opto22 or A-B.... you have to figure out precisely what's being done with this module before you can substitute another module for it.

JD, do you have specific Beckhoff modules you recommend for fast-pulse input or onboard boolean logic ? How fast can the EtherNet/IP adapter report back their status ?

flyers · May 19, 2011

Guys,

The 1771-IT is connected to the GEMCO high speed programmable limit switch (2500 rpm). The turn-on and turn-off time is 50 microsecond. An encoder is linked with the GEMCO. I think the normal 1756-IB16 module is not fast enough. So, is 1756-PLS the best replacement module to use?

For 1771-DS module, I'm still not clear the function of it.

Does this modules latch the input signal even if the input is a very short pulse of 0.1ms?

Thanks guys!

TConnolly · May 19, 2011

jdbrandt said:
Skip the nightmare, and use a Beckhoff BK9105 Ethernet/IP coupler and then just use the correct terminal module to do the work. I've just installed my first one, and after that experience, for-the-life-of-me, I just don't <<get>> why everybody wants to fit every problem into the Rockwell I/O module box.
Define the problem, and solve the problem with the right tools, regardless of the choice of processor.
IMHO, of course.

Absolutely.

We have been using Beckhoff BK9105 Ethernet couplers and terminal IO with controllogix processors for several years now. They are super simple to set up, very well priced (you'll be pleasantly surprised), and play well with the CLX. The update speeds are fast. Beckhoff US tech support is excellent.

flyers · May 30, 2011

Ken Roach said:
You have to investigate how these modules are being used in *this* application.

Using a 1756 discrete input module in the local chassis with the controller, and using the Change-of-State trigger for an Event Task will allow you to cover virtually all applications of the 1771-IT fast input module.

The 1771-IT had an input delay time of 0.6 ms +/- .2 ms, while the 1756-IB16 module has an input delay time of 1 ms Off->On, and 2 ms On-Off. If your inputs are longer than 2 ms then you're great... if not, then you have to keep looking.

The 1771-DS had some boolean comparison features and some extremely fast input filters that no modern module has. An encoder module, a 1756-PLS module, some networked module from Beckhoff or AMCI or Opto22 or A-B.... you have to figure out precisely what's being done with this module before you can substitute another module for it.

JD, do you have specific Beckhoff modules you recommend for fast-pulse input or onboard boolean logic ? How fast can the EtherNet/IP adapter report back their status ?

Guys/Ken,

Thanks for your info.

We'll be replacing the 1771-IT with 1756-IB32.

The 1771-DS will be replacing with 1756-PLS (input, output and encoder module), but we'll be using the fast input point of this module only. The output and encoder is not using. The machine will have a Programmable Limit Switch encoder (Gemco). After this is working fine, we'll upgrade and use encoder to replace the Gemco (optional step). The PLS output is 50microsecond, so I have to use 1756-PLS.

Any word of wisdom fro you guys?

Replacing PLC-5 with CLX - possible?

flyers

Member

MichaelG

Member

jdbrandt

Lifetime Supporting Member

Ken Roach

Lifetime Supporting Member + Moderator

flyers

Member

TConnolly

Lifetime Supporting Member

flyers

Member

Similar Topics