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Current Spike in a power supply...
- Thread starter box23
- Start date
box23 you have provided so little info... 
Tell us more about your load.
Tell us what part of the country you are in.
What kind of supply is it?
How is the load hooked to the supply?
How is the supply wired to its source?
Then we can get pretty specific in our help to you.
Keith Cress
Flamin Systems, Inc.-
Tell us more about your load.
Tell us what part of the country you are in.
What kind of supply is it?
How is the load hooked to the supply?
How is the supply wired to its source?
Then we can get pretty specific in our help to you.
Keith Cress
Flamin Systems, Inc.-
- Thread starter
- #3
- Moderator
- #4
Current is usually load dependant. A failed diode may cause your power supply to output high current.
A power supply fault, whether transient, intermitent or continous, or a power line transient may result in a voltage spike to the load. This may destroy the load or the diodes, and high current may be the result rather than the cause.
You will notice that I have used the word "may" several times. You have not provided enough information for the power supply experts like itsmoked to give a more definite answer.
respectfully
A power supply fault, whether transient, intermitent or continous, or a power line transient may result in a voltage spike to the load. This may destroy the load or the diodes, and high current may be the result rather than the cause.
You will notice that I have used the word "may" several times. You have not provided enough information for the power supply experts like itsmoked to give a more definite answer.
respectfully
Does this supply have inputs to control the output?
If so, are the wired to somewhere?
Tell me more about the load. Two diodes in series as a load makes no sense to me. (yet)
Keith Cress
Flamin Systems, Inc.-
If so, are the wired to somewhere?
Tell me more about the load. Two diodes in series as a load makes no sense to me. (yet)
Keith Cress
Flamin Systems, Inc.-
What do you have the current limit on the supply set to?
Setting the current limit on the supply to about 70 amps
should save the other diodes if one fails. If your load
is diodes then the voltage drop should go lower when they
heat up and then the supply will give more current,then
the diodes heat up more and so on.If I understand your load correctly.
Setting the current limit on the supply to about 70 amps
should save the other diodes if one fails. If your load
is diodes then the voltage drop should go lower when they
heat up and then the supply will give more current,then
the diodes heat up more and so on.If I understand your load correctly.
Hummm - you said it was a Sorensen power supply. The last time I was using Sorensen power supplies 20 years ago, the high DC current versions used a phase-angle SCR type rectification on the transformer output in order to be variable (I'm not sure what they call this kind of variable voltage method.) If the frequency of the main power input had a phase shift, this rectification/variable-voltage method could possibly create a transient on the output as the regulation circuit could not act very fast.
OperaHouse
Electrical
I would tend to think a high current power supply is designed around a specific voltage and overvoltage would not be high enough to cause damage. If your circuit is that sensitive, you should have OV crowbar protection. More likely the pulse is coming in through the ground and being induced into your circuit. Repeated failures and the same power supply surviving points to a problem with what you are doing, not to the power supply.
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