Yes, I did cringe at the mention of electric heat.
I have heard that VFDs cannot go below 25%, but my experience with VFDs on sump pumps is different. I have had no trouble running them from 5 to 15 HZ. I have been told that the minimum speed prevents the motor from overheating due to low flow...
We have a 3 story office building in Burlingame, California. I would like to activate the old (1968) HVAC system to heat (cooling is not too important in this location) 12 offices and a conference room. This is about 15 percent of the area served by the HVAC system. The system contains:
75 HP...
We have a 3 story office building in Burlingame, California. I would like to activate the old (1968) HVAC system to heat (cooling is not too important in this location) 12 offices and a conference room. This is about 15 percent of the area served by the HVAC system. The system contains:
75 HP...
Thanks again for thorough and useful responses.
Here is some more info:
Safety: Fortunately, we have a "never work live" policy. We lockout the hv power, lockout the secondary mains ( A generator hooked to the building wiring can generate hv if you do not do this. ) test for the...
I would like to thank the particpants for their long and well thought out responses. Here is additional information on our system, as well as a few more questions.
Spare parts. We currently have three 5000 ft. spools of XLP-PVC 5 KV wire mounted on spools in a truck ready to drive up to a pull...
The facility we have was the Mendocino State Hospital until 1972, when it was closed. I have done an extensive search of all maintenance records, there is nothing on the transformers. Quite a few records are gone. I suspect that they were packed up and stored in Sacramento somewhere. I will try...
we have a 2400VAC delta distribution system with 10 single and 12 three phase distribution transformers. the total kva is about 1000, but we only average 57 kw usage. the xfmrs range in age from 30 years to 100 years old. we are billed at 2400VAC with no penalty for power factor. i would like to...
