problem with pt100 signal on generator
problem with pt100 signal on generator
(OP)
I have two generators 1,5 mw on a vessel, and they´re are used to supply the generation plant for the vessel and two syncronous motor used for propulsion, the level on harmonics on voltage is not to big, ok, the problem is that with more than 50% of the load, the signal that comes from pt100 are getting a lot of noise and peak that makes the monitoring system to give a signal of error, i have connected other pt100 on the connections on the generator, and the measure is right... this make me think that i have some problem with the pt100 onto generator slot... but this problem occurs to all the pt100 and in both generators, maybe somebody could helps me in order to know why this is going on. thanks





RE: problem with pt100 signal on generator
David Castor
www.cvoes.com
RE: problem with pt100 signal on generator
RE: problem with pt100 signal on generator
Regards,
Jim
RE: problem with pt100 signal on generator
and the most important thing, how to solve? cause i can´t install a new sonda onto a wind, is it dependent on harmonics or just about magnetic field.
thanks
RE: problem with pt100 signal on generator
What happens if you use a multimeter measuring direct at the RTD - noisy or stable?
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If we learn from our mistakes I'm getting a great education!
RE: problem with pt100 signal on generator
RE: problem with pt100 signal on generator
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If we learn from our mistakes I'm getting a great education!
RE: problem with pt100 signal on generator
RE: problem with pt100 signal on generator
You should consider using an RTD isolator that will remove all of the common mode noise signal so your measurement system remains within its operating limits.
Keith Cress
kcress - http://www.flaminsystems.com
RE: problem with pt100 signal on generator
If you have a lot of harmonics then capacitive coupling may also be problematic. Can you get a 'scope to look at the input to the RTD signal conditioner? Be careful not to introduce an additional earth from the scope into the loop. If your 'scope has screen capture post an image or two.
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If we learn from our mistakes I'm getting a great education!
RE: problem with pt100 signal on generator
You say it's unstable when you measure directly at the generator does this mean the resistance reading is erratic?
If the RTD is grounded a 4-20 mA transmitter right beside the generator might help.
The wires should be twisted where under the influence of magnetic field for sure.
I haven't seen 100 Ohm Pt used in motors very often, usually it's 10 Ohm Cu with lower impedance.
RE: problem with pt100 signal on generator
Now the ship is sailing.. but i want to think about
RE: problem with pt100 signal on generator
If you can twist the leads as ScottyUK says I'm sure you will see a vast improvement.
Roy