Does anyone know of a method to measure the resistance of a long ground cable that has been installed?
The cable in question is a bare 4/0 copper cable installed in the concrete of a conduit bank. The conduit bank is about 2km long (1.2 miles) and I have to ensure the resistance is low enough...
Has anyone attended (or know someone who has) the Medium Voltage Systems School put on by TMEiC?
I am looking for feedback and whether or not it's worthwhile to send employees in my department; it's attractive as you only have to pay travel and accomodations but worry they will just push their...
I am currently working on a proposal to replace three (3) medium voltage (MV) full voltage non-reversing starters (FVNR) with VFDs.
The motors are 1250hp, 4000V, induction machines connected to large blowers. The client would like to reuse the power cables feeding the motors but I have a...
As a part of a project I am working on I have to size a generator.
The generator will be used as a standby power source, used only when utility goes down.
The primary function of this generator is to power a mine hoist to get men out of a mine. Secondary functions include dewatering pumps...
I am trying to find companies that manufacturer copper clad messenger cable.
The only company I have found so far is American Wire Group, and they seem to be just a distributor.
Thanks
Can anyone tell me if there is a standard or publication that goes into details for calculating the vertical lineal distance between cable clamps.
I need to confirm how many cable clamps I need for a vertically installed cable, vertical distance is approximatly 3200ft.
Thanks
Magnetic Forces on Cables During Fault
Can anybody explain the magnetic forces on a cable during a fault.
Trying to find information on single conductor cables installed in trefoil, single conductors installed with spacing, and three conductor cables.
Assuming this won't be an easy discussion...
Currently I am working on a job that requires the use of 316 stainless support brackets in a potash mine (exposure to water, high humidity, potassium chloride, sodium chloride, and magnesium chloride)
The brackets are of a critical nature, basically if they fail the mine will be shut down for...
This is a question about how to ground a DC system.
Currently I am looking at two options and I don't know which is the right way (is one right and the other wrong?).
First where the -ve of the DC is tied to the AC ground system.
The second is where the DC system ground is isolated from the...
Any issues with what I am describing below?
Basically I want to know if problems will arise by having my main site transformers which are connected to the utility at a Dyn11 and another set of Dyn11 stepping this voltage down some more and then another Dyn11 for the final distribution voltage...
Should be simple but I am not thinking quite right this morning.
If I am given a load and being told it requires 500kW how do I calulate the current it will draw? The load is for a large machine and will be mainly motor loads.
Would I take the 500kw divide it by the voltage * 1.73 * PF
Or do...
So I have an application that I am currently stumped on.
We have a 150HP motor, 575V AC, that we have to start multiple times each hours, could be as high as 25 starts each hour.
The motor is driving a rotary plough discharger which is started under load.
I have been having a hard time...
Has anybody had to deal with the grounding of Victaulic piping?
We are currently having discussion within our office on whether or not each section of Victaulic pipe has to be grounding to ensure that the whole pipe line is continuous. Some people are saying that the pipe coupling will isolate...
Ok, I always have problems with this and I will try my best to explain my question.
First let me state that the values I am using are just made up, I need this to click in my head so I am trying to keep it dirt simple.
To start I will state a few things, I have a transformer, it's a...
Ok,
Have a transformer rated for:
45kVA
Delta-wye
575-208/120
3 phase
I am limited to the use of J type fusing on the line side of this transformer based off Client standards,
Going through the calculations and using the Canadian Electrical code I come up with a 60A J-Type fuse.
When I look...
I have to show a braking motor on a single line diagram and I don't know and can't find any symbols that represent a braking motor.
The motor is an induction machine, 600V, 3-phase, across the line start, reversing, with a mechanical brake, from the way I understand it is that there is a coil...
I am currently looking at providing protection for a 200HP motor.
It is driving a vacuum pump.
When I sized the fuse according to the local code books one of the reviewers did not like my sizing because I did not take into account the type of load, being either a high inertia or low inertia...
Just wondering if the torque output on a belt drive is directly proportional to the ratio of the belt drive?
I have a motor with a rated speed of 1185 RPM and a pump with a rated speed of 372 RPM.
The rated torque of the motor is 1187Nm.
Would the torque applied to the pump be equal to...
Did not know where else to post this as there was no CEC in the engineering code section.
My question come with the spacing of equipment (rule 2-308 and 2-310)
The equipment I have (600V MCC) is rated at 1200A, according to 2-310(2) I need two exits or 1.5 meters.
My question comes with where...
Can anyone tell me if there are curves that show the starting of a pump?
I would like to know how long it is going to take for a certian pump to start based on being connected to a motor, so far the manufacturer has just given me motor information which has nothing to do with how long it is...
