Screw compressors only approach fla when they approach max psi.What pressure is it operating at and what is it rated at? Slight pulley changes allow for different cfm/psi configurations at a given hp.Reducing pressure will reduce current. Once you determine the pressure switch or regulator set...
we are going to correct the problem as follows:
1. install a 277V 15A resistor on the xo of the supply transformer,as there are no 277V loads on this transformer.
2. change out existing zero sequence monitors with trip setting of 3-5A, to an adjustable trip setting from .25 to 2A.
3. float xo at...
with dc motors volts=speed amps=torque. dc bridge motors are always connected in series. at least on the dc cranes I have worked on P&H, and Alliance. as one motor see's more load vvoltage across that motor drops, the balance of the voltage shifts to the other motor increasing its speed,and...
class 1 div. 1 or 2 = money, money, money. anything with this rating is expensive.there are some nfpa publications that clarify requirments. not for compressors but for motors, switches, etc.
I worked at a mine that blew up 2 size #6 starters in one night! the starters were on a 300hp vent fan on a bore hole. they started the fans in the wrong order and the chimney effect on the 300hp fan caused it to spiin backwards, when they tried to start it across the line it blew the door off...
I am not sure about the ins and outs of all things hydraulic but have worked on some pretty strange machines in the mining industry. here is an idea maybe you can run with it, on some drills they had a system called "paralleling automatics" which amounted to 2 identical cylinders installed at...
Bung,
I'll do the best I can, thanks for the input so far.
1. correct
2. correct, the nameplate on the resistor says 15A,600V only.
3. correct
4. correct, it is a dry-type winding.
I understand that the current is coming from the phases, I fail to see what role the grounding resistor plays in...
The autotransformer is supplied by a solidly grounded 480Y/277V 2000kva transformer. The ground fault monitors have a c.t. around all three phase conductors for that circuit, they are calibrated to trip at 3-5 amps. With this type of ground fault sensing shouldn't the relay trip even if the...
I have a 750kva autotransformer 480v/1000v, it has a 15a 600v resistor connected to the xo/ho terminal. The autotransformer feeds 2 400a/1000v breakers equipped with shunt trips and ground monitoring. I have experienced 3 faults with damage to a phase conductor in the trailing cable and the...
