Created Date: June 15,2012

Created by: Do-more PE

While we don't sell or service Honeywell Modutrol or Siemens, I can give you a few tips since I used to work on Modutrol motors fairly frequently.

This is a pretty common complaint with the Modutrol. Depending on how the wiring is ran from the SM332 to the Modutrol, it may be that there is the possibility for the wiring to pick up radiated energy from nearby lightning strikes which opens the resistor.

Also a common complaint on the Modutrol is that the slider that determines the motor shaft position gets dirty and quits reading correctly. I do not remember if this translates directly to the analog input for the motor or not.

Created Date: June 15,2012

Created by: dasrajib

Dear All

We are using Honeywell make Modutrol Motor (Model- M7284C1000) in our Burner system. The Modutrol Motor is acting as a damper actuator, it has been controlled by 4-20 mA which is outputted by Analog O/P Module( Model - SM 332).

We are recently facing problem in this system for few of our customers.

Problem: We are observing that whenever these Modutrol Motors become faulty like the modutrol motor stopped working on getting the mA supply from the Analog O/P Module, after a few days of time the Analog O/P Module started showing 'sF ' error LED ON and then we did not get the mA output from the Module from any of the 8 channels.

We have observed that:

I. For faulty Motor, the resistance between ‘+’ and ‘ – ‘ in the Terminal board of Motor is somewhere between ~ 5.1KOhm to ~ 56 KOhm.

II. For OK motor, the resistance between ‘+’ and ‘ – ‘ is somewhere between ~101Ohm and 120 Ohm.

My question is: In the present connection system of Analog O/P Module and Modutrol Motor, if Modutrol motor is faulty, can it also make Analog O/P module faulty? - which is happening for few of our customers.

We have thoroughly checked all the connecting cables- found OK.

Thanks

Rajib Das.