Movable Bridges - Wound Rotor Motors
Movable Bridges - Wound Rotor Motors
(OP)
What is the purpose of a primary resistor ahead of the thyristor controller? The resistor is rated at 100 amps and has a very small ohmic value of 0.089 ohms.
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Movable Bridges - Wound Rotor Motors
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RE: Movable Bridges - Wound Rotor Motors
"Venditori de oleum-vipera non vigere excordis populi"
RE: Movable Bridges - Wound Rotor Motors
RE: Movable Bridges - Wound Rotor Motors
RE: Movable Bridges - Wound Rotor Motors
http://www.filnor.com/html/products/motor.html
The only other possibility is that the motor nameplate voltage is lower than your line voltage, and they did this in an attempt to make it work. Given the short duty cycle of bridge crane motors, it is possible that it would work for a long time, although the motor would have permanently reduced torque. If on the other hand it were oversized for the application, that may have not been a problem either. It bears checking it out.
"Venditori de oleum-vipera non vigere excordis populi"
RE: Movable Bridges - Wound Rotor Motors
Thank you so much for the cross talk!
RE: Movable Bridges - Wound Rotor Motors
"Venditori de oleum-vipera non vigere excordis populi"
RE: Movable Bridges - Wound Rotor Motors
If this thyristor drive is of the 3-phase bridge type that drives a DC motor there has to be a deliberate resistance, inductance, or universal harmonic filter in the line to limit what happens during commutation. A 3-phase bridge rectifier (or inverter when regenerating) creates 6 short circuits every cycle because the thyristors do not turn off instantaneously. If you do not have this or the equivalent in a long branch circuit your thyristors will not live long.
It is now a well known phenomenon that when 2 bridge rectifiers are connected to the same bus without imdividual impedances voltage uncertainty when one rectifier is commutating will tend to burn up the other rectifier.