- #1
rioesmarex
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Electrical question:
I live in Mexico ( retired ex-pat ) and my electrical supply ( 240 volt single phase ) comes through a transformer that is almost 1 km away from my house. The supply lines are 2-0 aluminum.
Because of the distance and from usage by others on the line, the voltage is often low when it reaches me. To try and rectify this problem I installed a custom built step up transformer at my house prior to the power entering the distribution center. The transformer has taps to allow for incoming voltage as low as 175 volts and up through 230 volts ... The secondary side boosts the voltage to 240 volts ( or sometimes higher ) regardless of the incoming primary voltage.
Problem is that although I initially have 240 volts +/-, as soon as I draw power ... especially from pumps/motors/compressors, the voltage begins to drop drastically. The worst culprit is the well pump ... when we flush the toilet and the pump activates, and the voltage drops down low enough to kick in my generator when activates automatically when the voltage drops below 175 volts. Sometimes the pump will start and stop several times and the power surges each time, then it settles down and voltage returns to normal and the generator kicks out again. Other times it just bogs down at 175 volts and I have to manually open and close it's circuit breaker to get the power to flow again.
We have had this problem, on and off for several years, but to a lesser degree. Recently the power lines came down in a storm and the power company repaired the line and re-hooked my wires to the supply lines. The draw down in power seems to be worse since then
Several possibilities/questions"
1) If by chance the power company accidentally hooked my neutral wire to a hot leg on the supply line and vica-versa with a hot leg, what would happen ? Would this just kick a breaker somewhere, or would the system still work, but be the cause of my problems ?
2) In searching for the cause of the problem I notice that in my step up transformer, I have amperage draw ( 6 amps ) on the neutral output leg on the secondary side ...is this normal ?
... I have two hot lines ( Primary coming in ) and three secondary output lines ...2 hots and a neutral. The original Primary neutral goes directly to the distribution panel where it is then tied to the secondary neutral produced by the transformer.
3) Where should I set the taps on the transformer ? To match the incoming power supply line voltage, ( when all power is turned off, the incoming supply voltage reads 230 volts )... or to match the voltage when all the equipment is activated. When there is heavy voltage draw, a meter reading of the incoming supply line often shows as low as 175 volts.
Currently I have the taps set at 175 volts.
On a heavy load day with a.c. units on and swimming pool pump running and fans in the house etc. the individual units together are tag rated at approx 45 amps. When the well pump kicks into flush the toilet, the pump theoretically adds another 10 amps to the load
... total 55 amps.
I have a 200 Amp service panel ... the step-up transformer is rated at 25 Kva ... and the breaker panel down the line ( 1 km away next to the main transformer ) is rated at 150 amps and the main transformer itself is 75 Kva.
Other than the three possibilities I have posed does anybody have any ideas what is causing
the huge voltage drop as heavy circuits are energized.
Sorry for the long post, but better to explain the problem in detail
I live in Mexico ( retired ex-pat ) and my electrical supply ( 240 volt single phase ) comes through a transformer that is almost 1 km away from my house. The supply lines are 2-0 aluminum.
Because of the distance and from usage by others on the line, the voltage is often low when it reaches me. To try and rectify this problem I installed a custom built step up transformer at my house prior to the power entering the distribution center. The transformer has taps to allow for incoming voltage as low as 175 volts and up through 230 volts ... The secondary side boosts the voltage to 240 volts ( or sometimes higher ) regardless of the incoming primary voltage.
Problem is that although I initially have 240 volts +/-, as soon as I draw power ... especially from pumps/motors/compressors, the voltage begins to drop drastically. The worst culprit is the well pump ... when we flush the toilet and the pump activates, and the voltage drops down low enough to kick in my generator when activates automatically when the voltage drops below 175 volts. Sometimes the pump will start and stop several times and the power surges each time, then it settles down and voltage returns to normal and the generator kicks out again. Other times it just bogs down at 175 volts and I have to manually open and close it's circuit breaker to get the power to flow again.
We have had this problem, on and off for several years, but to a lesser degree. Recently the power lines came down in a storm and the power company repaired the line and re-hooked my wires to the supply lines. The draw down in power seems to be worse since then
Several possibilities/questions"
1) If by chance the power company accidentally hooked my neutral wire to a hot leg on the supply line and vica-versa with a hot leg, what would happen ? Would this just kick a breaker somewhere, or would the system still work, but be the cause of my problems ?
2) In searching for the cause of the problem I notice that in my step up transformer, I have amperage draw ( 6 amps ) on the neutral output leg on the secondary side ...is this normal ?
... I have two hot lines ( Primary coming in ) and three secondary output lines ...2 hots and a neutral. The original Primary neutral goes directly to the distribution panel where it is then tied to the secondary neutral produced by the transformer.
3) Where should I set the taps on the transformer ? To match the incoming power supply line voltage, ( when all power is turned off, the incoming supply voltage reads 230 volts )... or to match the voltage when all the equipment is activated. When there is heavy voltage draw, a meter reading of the incoming supply line often shows as low as 175 volts.
Currently I have the taps set at 175 volts.
On a heavy load day with a.c. units on and swimming pool pump running and fans in the house etc. the individual units together are tag rated at approx 45 amps. When the well pump kicks into flush the toilet, the pump theoretically adds another 10 amps to the load
... total 55 amps.
I have a 200 Amp service panel ... the step-up transformer is rated at 25 Kva ... and the breaker panel down the line ( 1 km away next to the main transformer ) is rated at 150 amps and the main transformer itself is 75 Kva.
Other than the three possibilities I have posed does anybody have any ideas what is causing
the huge voltage drop as heavy circuits are energized.
Sorry for the long post, but better to explain the problem in detail
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