I've been thinking about my own question. Perhaps if I connect the negative terminal (-) of the DC source in the earth and the positive terminal (+) in the cable sheath, and because the electrons flow from the (-) to (+), i'm not be able to detect a defect in the insulation of the cable. Am I...
Hello!
I'm performing DC test to verify the outer sheath integrity on a MV 36kV cable after laying, according to IEC 60840 & IEC 60229 standards. I'm using a BAUR testing equipment. According to the manufacter, the test equipment negative (-) terminal should be connected in the outer sheath and...
Thank you davidbeach.
I think the Line Trap should be a LC low-pass filter to allows the power frequency to enter in the substation, and the CCVT must have a band-pass filter or a high-pass filter, in that case i'm not sure, because the PLC frequencys, I think I've read this somewhere, came in...
Hello,
I'm very interested in PLC systems. I have a Line Trap and a Capacitive Coupling Voltage Transformer installed in a 220kV substation.
I would like to apply the formulas and get the values that leave me to understand how these system works. Where could I find a good guide to sizing and...
Hello
Testing a HV Voltage Transformer, using a OMICRON equipment (that must be connected to earth) I must inject in the primary side a test voltage, and I want to check the phase-angle in the secondary of the VT. Why the phase-angle should be near zero volts?
Thank you in advanced
Hello everyone,
I'm testing a 220kV Voltage Transformer with a CPC100 Omicron device.
One of the test that i've to perform is the phase checking. I've a three-phase VT of a bank of three single phase VTs.
I'll do a primary injection and measure the voltage between phases and neutral in the...
Thank you Scottf for your kindness and patiente. And what could cause the "float up" at the seconday winding potential? Could you give pratical or possible examples? Phearps and induction current that appears in one of the seconday cables cause that "float up".
Hello again. I would like to understand better this poiny of the secondary of the CT, grounding.
ScottyUK (Electrical)5 Mar 15 13:12
The CT secondary circuit forms a closed loop. The loop is connected to earth as a reference at exactly one location. No current flows to earth, it just provides a...
I agree with you marks1080, and I don't feel confident in perform these tests, but I have to do it, and I don't have nobody in my company to explain me. And studing these the better way I can...
Hello,
I've uploaded the diagram in order to be more clear in my doubts.
CT:
400A/1-1-1-1
Step 1:
Injection of 200A in the primary of phase "0"
Confirm that in the terminals X1:25/28 of the marshalling box I will have 0,5A
What should be the value of the current between X1:25/29?
Step 2...
Hello,
Please find attached the diagram were you could see the marshalling box connections.
Could you please help understand the function of the PHOENIX SB2-RTK/S and SB4-RTK/S slide bars?
After the CT tests are donne, and if all the secondaries of the CT are used, these sliding bars should...
Ok. Tomorrow I will place a schematic here.
But the PHONEXI CONTACT URTK/S BEN with PHOENIX SB2 or SB4-RTK/S were use only for testing proposes, right?
Thank you in advanced.
Hello every one,
I've a CT marshalling box that getter 3 CT's (one for each phase).
These box received the wiring cables from each CT secondary terminal box and from that marshalling box it'll be connected the cables that goes to the meters and relays installed in a control house.
To connect...
Ok. So in pratical terms when I place a multimeter in the terminals (related with the N1 secondary) in the marshalling box the current will mark 0 Amps because most of the current will circulate in the loop made in the correspondent secondary at the CT terminal box. Then when I remove the shunt...
Hello again everyone.
I'm studing the CT testing issue, because a I've to prepare the tests to go on site.
I have to test a Multi-core CT: 400A/1-1-1
secondary N1: metering
secondary N2: protection
secondary N3: protection
The secondary nix of the CT is connected to a marshalling box that is...