×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Woodward SPM-A Synchronizer output

Woodward SPM-A Synchronizer output

Woodward SPM-A Synchronizer output

(OP)
I have a Woodward SPM-A 9905-001 synchronizer on my system. I am trying to use one of the three outputs (Low Impedance, High Impedance or EPG) to send a signal to my engine control to speed up or slow down the generator.

I am having a heck of a time finding out what type of signal each of these outputs puts out. The vendor info does not specify what these signals are other than high impedance, low impedance.

I suspect that the signal is a +- 5VDC for +-3.5% speed change, but I'm not sure.

I also have a vendor looking into this, but not having much luck.

Anybody out there know what type of signal the synchronizer puts out? (Terminals 20-21 or 21-22 or 23-24)

For those of you who want to suggest for me to look at the Woodward manual #82384, I already have. It does not have the information I am looking for.

RE: Woodward SPM-A Synchronizer output

Does this help?

Both synchronizers versions have three output options: high impedance, low
impedance, and EPG. Select the high impedance output for single-unit
synchronization when the engine is controlled by a Woodward 2301 control.
Select the low impedance output for single-unit synchronization when the engine
is controlled by a Woodward 2301A, 2500, or Electrically Powered Governor
(EPG) control through a Generator Load Sensor. Use the EPG output when using
a Woodward EPG control without load sensing.

from Page 2 of Manual 82384, I have Revision R.

Mike L.

RE: Woodward SPM-A Synchronizer output

If you use the low impedance connections into a 2301A it is plus/minus 2.5 VDC to get plus/minus 5% speed change

The older 2301 was something close to 1VDC was about 1% speed change, but I not in the office and don't carry the old info around with me.

What governor do you have?

Mike L.

RE: Woodward SPM-A Synchronizer output

(OP)
Thanks mike. I'm actually trying to interface to a non-Woodward engine control based on Allen Bradley 4-20 mA analog. Knowing the range I should be able to obtain a voltage to current converter.

RE: Woodward SPM-A Synchronizer output

Depending on the prime mover you're trying to control, you likely won't be happy with the results, unless you have a nice stable bus and a pretty stable genset. The Gain and Stability range on the SPM-A is not very broad and is targeted around the response characteristics of the Woodward governors. I have been involved over the years in a number of projects trying to use an SPM-A into PLC based controls systems, most using gas engine prime movers and most not meeting customer needs.

If you need a synchronizer with a broad application range and a direct 4-20mA output, use an SPM-D. I'm guessing you already have the SPM-A and are trying to upgrade or change existing? I think you'll find the cost of the SPM-D better than the time and effort you will spend trying to get the SPM-A to work, unless you're luckier than I am.

Mike L.

RE: Woodward SPM-A Synchronizer output

(OP)
I'm trying to sync a gas recip onto an islanded bus. The engine is not the most stable but we have the fuel valve tuned down so response is slow. We usually run the unit in fixed kilowatt mode. We have two jets which run in Isoch, and take up all the load swings.

I will look into the SPM-D thanks!

RE: Woodward SPM-A Synchronizer output

If you are trying to sync a gas engine onto an islanded bus I would definitely try an SPM-D, and use the Slip mode instead of phase match, think you'll find the results much better.

Mike L.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources