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Subject - three phase voltages
taperule44 In three phase 208 the voltages line to line are 208 yet the voltages line to ground will be 120,120,and 208. The 208 is called the striker voltage I think. What is the purpose of the striker voltage?
kbsparky IF you have a delta connected (high leg) system, then the measured voltage from line to line should be 240, not 208. The high leg itself will measure 208 to neutral or ground, but the other 2 legs will measure out at 120 to ground.

Some other names for the 208 Volt high leg are: Stinger leg, wild leg, etc. It should be marked orange and installed in the center position in 3 phase equipment.
Electricman The poco in my area always brings the high leg into the CT can on C phase, I asked the engineer why and he said cause thats the way we do it He said once I bring it into my switchgear he said I can put it on B phase if I want and that it didnt matter to him either way. Is this a common practice from utity providers?
kbsparky Yeah, one of our loco utilities also requires that high leg to be installed on the "C" phase position in the meter box.

As long as we terminate it into the center position on our equipment, all is well
Electricman I do remember that the utility guy did say that the meter would not work right if the high leg wasnt on C phase.
lctrc789 A 3 phase OPEN DELTA can give you 240 volts line to line.
Some power comapnies do this to get single phase and 3 phase loads. Center tapping these gives you these values.
kbsparky
quote:
A 3 phase OPEN DELTA can give you 240 volts line to line.
Some power comapnies do this to get single phase and 3 phase loads.


And all this time I thought they were trying to save some money by only having to install 2 transformers instead of the usual 3. And, "cheating" by only connecting to 2 of the phases, especially in remote or rural areas where all 3 phases are not readily available.

I have seen both open-bank delta connected and closed bank delta connected systems that have the same output voltages available, including both single and 3 phase connections from the same transformer bank.

Chris Clement They are electrically equivalent but 2 pots are cheaper when the load doesn't warrant all three.