Machine Voltage Stability

Status
Not open for further replies.
D

davet

Member
240V./3phase/4wire panel feeds a 3 phase machine with internal control xtrf.stepped down to 120V.One side of control xtrf. grnded to machine. No neutral present.
Customer notices pc setting output suddenly varies.which effects quality.Must re-adjust pc on the fly.I am considering to install a xtrf. on the feeder to machine.Is this practical?
Q? What type of xtrf.would be required to stabalize the 240v.to machine or are there other optins available.
Thanks.
 
Not sure but............

Not sure but............

davet said:
Q? What type of xtrf.would be required to stabalize the 240v.to machine or are there other optins available.
Thanks.
Click to expand...

A transformer will not help you......It sounds like you are having a voltage problem due to sagging or spiking.I'm not familiar with an exact product, but some kind of voltage regulator would definitely help . I am thinking of something like I have on my home entertainment system (it would probably be beefier for your application).
 
090405-1451 EST

davet:

What does this mean:
Customer notices pc setting output suddenly varies.
Click to expand...

What does PC mean? Personal Computer, or Programmable Controller?

What is "setting output"? Is there some digital (number) or analog knob in this PC thing that in some way sets an output? What is the output?

What does this machine do and how does the setting affect the machine output?

If you really have a supply voltage variation that causes the problem and not a ground path noise problem, then I might suggest a Sola type constant voltage transformer, and in particular a Sola brand unit. These are also known as ferroresonant transformers. This would only supply the PC thing if that is really where the problem originates.

.
 
Were I to guess (and I am doing so now) I'd say "PC" is supposed to mean Power Controller, as in an SCR Power Controller that is trying to maintain some kind of specific output voltage on a heating system. Most likely they have an el-cheapo version that has no regulation, so when the control power transformer draws current from 2 of the phases, it creates a voltage imbalance. The Power Controller cannot adjust to the imbalance maintain a steady output. This is a very common problem and is the reason why better Power Controllers have what is called "Voltage Regulation". They will basically equalize the output on the other phases to match the lowest detected input. That's the best way to approach this, you will throw a LOT more money at the incoming power side to try to stabilize it.
 
voltage stability

voltage stability

In regards to my question, PC = Programmable Controller. Output varies at times. Would replacing the control xtrf.with an isolation type be helpful?
 
090406-1509 EST

davet:

What output? Is it an analog output? Or digital? Or something else?

What brand of PLC? What are its input voltage specifications? I would expect the design should be good down to 95 V.

If the input power supply variations to the PLC are really the problem, then a small Sola Constant Voltage Transformer should solve the problem. These transformers may need a minimum load, and also to reduce wasted power they should not be oversized.

.
 
Voltage Stability

Voltage Stability

Thank you Gar. I will look into this more. You mentioned Sola Constant Voltage Transformer.
never heard of it.Could you direct me to it for explanation and distributors?
Thanks
 
davet said:
240V./3phase/4wire panel feeds a 3 phase machine with internal control xtrf.stepped down to 120V.One side of control xtrf. grnded to machine. No neutral present.
Customer notices pc setting output suddenly varies.which effects quality.Must re-adjust pc on the fly.I am considering to install a xtrf. on the feeder to machine.Is this practical?
Q? What type of xtrf.would be required to stabalize the 240v.to machine or are there other optins available.
Thanks.
Click to expand...

Isn't it possible to feed this PC from a sourse that isn't corrupted?
 
Status
Not open for further replies.
Top