OK…I’m an electrician, not a control technician…not that it would stops me from working on the stuff, but I admit to being on more than one learning curve…this week it’s been trying to figure out what’s wrong with one particular UDC 3000.

The application is simple…maintaining the level of a 400-acre lake…the system is comprised of a MTU (Control Microsystems TeleSAFE Micro 16) located at the Marina (near the dam) and a RTU located at the head gate. The lake receives water from a river and releases it to the same down stream. There are UDC 3000’s at both ends, however as the set point is managed by Lookout, the controllers just provide local control and display the set point and gate opening – the system was designed to have the controllers maintain the set point, but with Lookout they are redundant.

This is where it gets really simple – the set point is the gate position, not the flow or rainfall or some other more worthy variable. Open the gate x amount for x period.

The UDC 3000 at the head gate long ago had the input disconnected – presumably to solve the same problem I having. It appears as if the value in the UDC 3000 at the Marina had its value changed – there was a com failure (loose cable) and some undetermined fiddling took place. Now when the UDC 3000 is in Auto it interferes with the Lookout programming. I have recorded all of the settings in the controller and referred to the documentation (the only available documentation is for the UDC3300…apparently close enough).

This is where being a sparky, not a propeller head comes in…I’m having trouble making sense of the documentation…I think is assumes that you have to know something about what your doing. What I need to identify is the value that drives the output…. so I can put it to sleep. I believe it is SP HiLIM, but I want to be sure as I intend to write up the procedure to save the next poor fool that time and hair pulling.

 

You have given some good problem definition. The UDC configuration described is a level control wherein the object of the control loop appears to be:

Adjust the head gate position to maintain reservoir level.

This control occurs at two places on the reservoir: Inlet Flow and Outlet Flow. The inlet control is likely configured for reverse operation (increaed level decrease output, close gate). The outlet control is likely configured for direct operation (increased level increase output, open gate).

The set point should be the desired level of the reservoir. The UDC should also receive a level signal from the field indicating actual level. In Automatic mode, the UDC calculates controller output (via PID control), continuously. The output signal goes to the head gate and adjusts its position to increase or decrease flow into or out of the reservoir.

Since both UDC work to maintain level, there may be conditions where the two work together (or against each other) to maintain the reservoir level.

Since the two can be connected through Lookout, you may consider implementing a staged control wherein the downstream UDC handles a majority of level changes in the reservoir (small deviations in level). The upstream UDC could be configured to curtail inlet flow when level disturbances are larger and/or sustained over time (after the downstream UDC has reached open end point).

 

First mention your complete model no. of UDC3000 and send the configuration details. So that i can help you to resolve the problem.

 

Thanks for the reply. Here are is the model number and settings. Please note that the headgate is open 7ft at 100%. My most recent change was to set OUTHiLIM to zero so the controller does not output. However, when the gate is at 100% (7ft) we are getting an IN1 RNG ERROR. Could this be a span problem?

UDC 3000 Versa Pro UDC 3000
DC 300C-0-0A0-21-0000-0
S/N 9651Y628672300008

TUNING PROP BD
or
GAIN 1.0
or
GAINVALn Read Only
RATE MIN 0.0
RSET MIN 1.0
GAIN2 N/A
RATE2 MIN N/A
RSET2 MIN N/A
SECURITY 0
LOCKOUT NONE
AUTO MAN ENABLE
SP SEL ENABLE
RUN HOLD ENABLE

SP RAMP SP RAMP DISABLE
SP RATE DISABLE
SP PROG DISABLE

ADAPTIVE ADAPTIVE DISABLE

ALGORTHM CONT ALG PID A
INPUT 2 N/A
OUT ALG CURRENT
TIMER DISABLE

INPUT 1 DECIMAL XXX.X
UNITS NONE
IN1 TYPE 4-20mA
XMITTER1 LINEAR
IN1 HI 7
IN1 LO 0
BIAS IN1 0
FILTER 1 1
BURNOUT1 NONE
PWR FREQ 60HZ
LANGUAGE ENGLISH

CONTROL PID SETS 1 ONLY
SW VALUE N/A
SP SOURCE 1 LOCAL
SP TRACK NONE
POWER UP MANUAL
SP HiLIM 7.0
SP LoLIM 0
ACTION DIRECT
OUT RATE DISABLE
OUTHiLIM 100.00
OUTLoLIM 0
DROPOFF 0.0
FAILSAFE 0.0
MAN OUT 0.0
AUTO OUT 0.0
PBorGAIN GAIN
MINorRPM MIN

ALARM A1S 1TYPE NONE
A1S 2TYPE NONE
A2S 1TYPE NONE
A2S 2TYPE NONE
AL HYST 0.1

CALIB CAL IN1 DISABLE
CURRENT
ZERO VALUE 387
SPAN VALUE 1902

READ STATUS VERSION 31 11
FAILSAFE NO
RAM TEST PASS
CONF TEST PASS
CAL TEST PASS
FACT CRC PASS

 

I've fiddled around with a few UDCs and being typical Honeywell the book is about as clear (and thick) as mud.

SPHiLim is the parameter that determines how high the setpoint on the controller can be wound up to.
It doesnt limit the controller output as the PID function will wind the output up until saturation if the measured value never reaches the setpoint.

The 'Rng1' error your getting refers to the analogue input (UDC's are twin-loop controllers though in your application loop #2 is disabled)
It shows that error when the input range goes above 20ma or below 4ma.


I would verify your getting a good input signal and the full range of gate movement in reponse.

Put the controller in manual and wind the output up and down while watching the measured value.
Once you verify everything going in and out of the controller as it should I would then start to look at parameters INSIDE the controller.

P.s. SpHiLim might actually be in %, I cant remember if you can swap the display to show Engineering Units and % as the SP or not.
If so, setting it at 7 is bad if its displaying %.......

Try those and reply if its still not working.
I would like a little more clarification on what your measuring and what your controlling - 'gate position' is pretty hard to measure unless you have some sort of valve positioner arrangement.

 

hi,

i need to get a owners manual on this honeywell controller - can anyone help me?

thanks

Patti

 

Hi Patti

The bound manual you are looking for is Product #51-52-25-07E. Perhaps you could order one from Honeywell.

Hope this helps.

 

Patti,
You can access the PDF UDC 3000 Manual at the following:

http://honeywell.silverw.com/docs/51-52-25-07F.PDF

or contact:

www.convectorcontrol.com

Hope this helps,

darren