Okay, now you got me curious, I have seen some PC's running Linux as data recorders, but they needed quite a bit of additional hardware for A/D conversion.
I have picked up some arduino boards and SD card shields to take a crack at a home brew version just for sh*** and giggles, but never...
Oh, didn't catch your post before I reposted. So that may not make a ton of sense.
What is your choice for voltage dividers? We have used some Northstar VD Series (VD60's) on some medium voltage applications, but they are big, bulky, hazardous to touch potentials. I considered using...
I work at an electrical testing and engineering company, and we can and will find out why, unfortunately (at least for the end customer) it takes time and money. Often more than the equipment costs outright to replace.
Heh he, yeah, I hear ya. So far though, I haven't found evidence of other users with the problem. You know, you start typing your problem in the search box and it autofills with your issue.
It's in a BIG corporate's BIG plant, and there is some real consideration going on to "find" the...
Has anyone else experienced pre-charge resistor fail in ABB ACS800 VFD's. Our particular model is 400 A 575 Volt. The pre-charge resistor is 3.3 ohms 65 watts and is always left in the circuit, under the assumption that the half wave rectifier diode that is in series with it will not be...
You need to consider the bigger picture. When you consume power through L1 or L2, the circuit must be completed with a return path. The neutral.
Current comes in on L1 or L2 and goes out on the neutral.
Great. The ground conductor is there as an emergency path for a wayward L1 or L2...
In UL 845 (Harmonized UL, ANCE and CSA LV MCC's Standars *US, Mexico & Canada*) states the following:
"5.3.1.2 In the United States, the supply rating of equipment that is marked to indicate it is suitable for use as service equipment, has provision for 2 watt-hour meters without provision for...
Attached is the motor vendor data sheet. 94 and 91 percent efficient 4pole / 8pole.
The 17x figure, do you recall the lead-up, background and source of this new rating?
Thanks for you help so far...
The real question is, what other equipment of concern does the voltage dip affect. It's a question of what other stuff on the bus will be affected negatively if the bus voltage drops too much. For instance your point of common coupling with the utility. Utilities don't like to see voltage...
Has anyone experienced tripping of a magnetic overload protector in a 2 speed motor starter when switching from low to high speed. The units in question have a 3 pole contactor for low speed and a 5 pole contactor for high speed.
This is a new installation with new contactors and motors...
I am really happy to have all this feedback. catserveng has provided pretty much the exact feedback that I was hoping (expecting) to hear. The skiddish reaction of various parties echo the same things I am hearing.
I thought about the transfer system as well, and agree that it will be...
Thanks waross.
You have added valuable feedback to what I suspect would work. 110 - 125% would make a very efficient system.
Have you seen or know of any examples of this configuration that are documented, any related technical articles or units presently in operation?
I have read a...
An existing centrifugal water pump requires 3458 lb-ft of torque at 100% speed (1182 rpm)
It's WR^2 is 215 lb-ft^2
It is presently operated by a 900 HP, solid shaft, 1185 rpm (6pole) vertical induction motor. 4000V, 3 phase, SF 1.15
Present starting method, across the line, utility...
