voltage sag location in circuit capture
voltage sag location in circuit capture
(OP)
Consider a typical 480V 3P distribution system. A loose / high impedence connection is causing momentary voltage sags during the intermittant arcing. (Not a line to ground or phase to phase fault) I know these voltage sags are detectable downstream of the loose connection, however, are they present upstream of the arcing? Could they be detected on the upstream bus of the loose connection causing the voltage sags?
Thank you.
Thank you.






RE: voltage sag location in circuit capture
There will be a change in the current upstream. Depending on the how much the current change, the voltage may change. Voltage change will not be same as what the load sees, as there is no "voltage drop" upstream per say.
By the way the hypothetical condition you describe will not last long and the loads will not operate if they don't get adequate power supply. Arcing generates intense heat that usually turns in to insulation failure and much more, pretty quickly. Loose connection without arcing is bad enough.
Do you have a real issue at hand?
Rafiq Bulsara
http://www.srengineersct.com
RE: voltage sag location in circuit capture
RE: voltage sag location in circuit capture
If the load itself is not affected (which should be most obvious alert), I doubt you could detect much upstream.
It would help if you can throw more light on your background and what you are after, someone else may be able provide more useful information.
Rafiq Bulsara
http://www.srengineersct.com
RE: voltage sag location in circuit capture
Rafiq Bulsara
http://www.srengineersct.com
RE: voltage sag location in circuit capture
Typical features may be;
Voltage monitoring.
Shutdown on low voltage (adjustable set point)
Shutdown on voltage unbalance (adjustable set point)
Time delay after a power failure.
Contact monitoring and shutdown on the event of an open or high resistance contact.
A 25 event memory.
Phase loss protection.
There are several manufacturers to choose from and variations in features.
Bill
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"Why not the best?"
Jimmy Carter