Woodward Easygen vs PLC control system

[meehd88]

I am a facility owner currently working on replacing our genset and paralleling switchgear with 6 x 2.5MW CAT 3516c and am being presented with some options on the controls side.

Option 1 - Woodward Easy Gen + SEL 700G for UV/OV protection, sync check
Option 2 - CAT OEM EGP paralleling controls
Option 3 - Russelectric with Allen Bradly PLC + SEL 700G

I am looking for feedback on the options above in terms of reliability and would like to see if there are better options out there today. Main concern is reliability and serviceability. Cost is less of a issue.

 

[TE163]

I can't speak to the other units but I've been very happy with the SEL products.

 

[FreddyNurk]

My personal preference on any of this is go dedicated hardware rather than a PLC. For the examples you've provided this would mean the EasyGen option.
The previous Woodward model was the default standard for quite a few remote power stations I'd been involved in. I've not used them but the EasyGen also comes in a full redundant controller option if required.
SEL makes good equipment too, and has excellent support.

 

[TugboatEng]

The Caterpillar advantage is their local dealer network. Same day service is often available.

The Caterpillar disadvantage is that you may need to take advantage of that service. The OEM packages have to be more inclusive of a broader range of requirements so they tend to be more complicated as a result.

 

[dpc]

If the PLC is to be involved in generator synchronizing, I'd be concerned - they are generally too slow. Woodward + SEL would be my preferred solution.

 

[wcaseyharman]

In 2023 we had a contractor install an Easy Gen and we installed a 700G and a Basler DECS 400 on a 2.5 MW MP45 that powers a microgrid.

We are pretty happy with it.

We have a site with old Caterpillar controls, it seems very confusing to troubleshoot.

Granted, we were heavily involved in the easygen installation so we are much more familiar with it, but it’s worked very well for us.

I will say the easygen custom logic can be quite convoluted and the modbus tag list can be confusing, but it’s a capable box and is pretty flexible.

We have had good luck with PLC based hydrogovernor controls systems, but we’ve never used a PLC based control system for a diesel. The downsides of PLC based systems seem to be they often have limited electric based I/O, so you need voltage, current and power transducers separate from the PLC rack. Synchronizing is typically done by a separate box (now commonly in the relaying or excitation).

Based on what I know, I’d probably go with the Woodward since it’s pretty common and you’ll be able to get support from multiple companies.

 

[catserveng]

Before you can get a really good recommendation a lot more info would be needed about your system.

Based on your provided info I'd assume this is a standby system with some level of redundancy. But does it only operate as a standby system, or do you expect it to do more?

Is it required to parallel to the utility, either for closed transition return to utility, or some form of demand response?

Will it currently or in the future be required to parallel with other power sources, such a solar arrays, battery systems, fuel cells, etc?

I'd assume that the gens are fitted with medium voltage tailends, but that is not always the case, what is the generators rated voltage? Medium voltage systems tend to require more extensive electrical protections that the EasyGen may not accommodate.

Does the system replace power to a distribution bus (or multiple busses)? Or does it supply multiple ATS switches throughout your facility.

Most systems I work on in this size range use a combination of a Master control based on a PLC, each generator section fitted with a Woodward synchronizer/load control module and a multifunction protective relay, and other controls and protections as required by the overall system design.

A large majority of the systems I was involved in were based on the older Woodward DSLC/MSLC or DSLC2/MSLC2 sync and load share controls. I have done a lot of projects with the EasyGen platform as well, my own preference with the is the backpan mounted 3500XT module, I have run into some reliability issues with the 3400XT type (front panel mount), many of the issues depending on the environment the controls are mounted in.

The EasyGen is a very capable platform, but in asking it to do everything requires an extensive amount of programming and serious shakeout during commissioning, a large number of service calls I did over the years were mainly due to configuration issues. My experience is that with fairly simple systems an EasyGen can "do it all", more complex systems require possibility of needing additional levels of protection, sequencing, remote monitoring and data collection.

Hope that helps, MikeL.