Hi,
There is a parameter on the HMI screen that reads Input Kw and is a live figure as far as I can see as it moves up and down.
Does this figure give the overall KW usage on the circuit ie can this figure can be used as your consumption figure or cost figure?
Any help is appreciated,
Thomas
Hi there,
I am trying to determine the actual Kw cost of a motor being run via a VFD.
Where is the best place to measure the values I and V as there is differnces on the incoming supply to the load side of the VFD?
Thanks in advance.
Thomas
Hi anoter,
The cable is 4core 50mm so I reckon we are too small with the SWA lugs as you state. Its possible that the Electricains have had to cut out some strands to get the core into the lug. Would this causing arcing and overheating in your opinion.
I'll attach that pdf again.
Cheers...
Anoter,
Sorry wrong data sheet. See file for Lug data sheet.http://files.engineering.com/getfile.aspx?folder=6a825560-17e9-4b10-a502-f49c09b2c94a&file=page_889+890_1.pdf
Anoter,
When we changed the Isolator we re-lugged the cable therefore a crimping issue would mean two different Electricians crimped incorrectly. We have been onto the cable supplier and they are recommending different lugs. See attached data sheet. I have been trying to find out from them what...
Hi anoter,
Yes the field isolator is a switch for the motor before it enters the HVAC enclosure. I feel you are correct in suggesting the lugs. The Olflex I think is a type 7 stranded cable and I think the lugs used are for SWA which I think is a type 4 strand.
The high temps are occurring at...
Hi,
We are using a 4 * 50mm Olflex cable from a VFD via a Field switch Isolator to a HVAC Fan motor. The motor is running at 130amps Full Load Current.
We are experiencing very high temps at this field Isolator and I was wondering if anyone has come across this issue before with this cable...
The fan is controlled by a VFD. I had one of our automation guys take a look at the issue and he is happy with the set-up. It does take some time to smooth out the control but he reckons this 50pa drop in the first place is where the problem lies and slowing down the PID response may be just...
Hello there,
Let me give a brief history of the issue:
Our HVAC runs at 900 pascals supply static pressure set-point and our supply fan maintains this just fine. At irregular intervals however we have a sudden dip in pressure of roughly 50 pa and the fan will ramp up to counteract and it will...
All,
Thanks for the help. I've been off sick so didn't get back to you all. I've decided to get an allignment expert in to start from scratch. All currents and frequencies will be monitored.
And just for 'itsmoked' I've bought a lovely pair of red braces for my pants!!
Thanks again for all...
Hello,
Just curious as to the intervals of checks on belts are for different plants. We run HVAC units on belt systems 24/7 on motors on average of 75kw and we have an interval of 6 months. I'm beginning to suspect this is not ample as we are experiencing belt failures.
Kind regards,
Thomas
Hi Tmoose,
These are actually old units and I have little in the way of specs. The fan and motor are kept in an air stream chamber of roughly 14 degress celcius.
Cheers
Thomas
Thanks Wes,
I'll have a look around and see what I can dig. Do you have your own SOP for this? What are the chances getting a look at that?
Company policy permitting of course....
Regards,
Thomas
Thomas
Hello Jay,
I'm in the process of writing up a standard operating procedure for the allignment of pulleys and shafts. did you manage to get much literature on this issue. any help would be great.
kind regards,
Thomas Byrne
