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MOTOR CONTROL

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INTRODUCTION RARA can design and build motor control resistors of any type for any application, including:  Wound-rotor AC motors with slip ring starters, DC motor starters, Field discharge resistors, Torque-increasing resistors for use with soft starters and other similar applications. -custom designed for your particular system -several stages of assembly depending on shipping needs

STARTING RESISTOR WITH CONTROLLER

GENERAL SPECIFICATIONS

Model No.	Motor 2ndary Voltage	Motor 2ndary Current	Control Step	Motor Power
SRI(SRO)-5N	2000V max.	200A max.	3 to 4 steps	<200kW
SRI(SRO)-6N	2500V max.	400A max.	5 steps	500kW
SRI(SRO)-7N	2500V max.	600A max.	6 steps	750kW
SRI(SRO)-9N	3500V max.	1000A max.	8 steps	1000kW
SRI(SRO)-11N	4000V max.	1500A max.	10 steps	3000kW

CALCULATIONS

Minimum Information Needed for Model Selection:

1. Motor Power ________(kW),  2ndary Voltage ________(V₂),  2ndary current ________(I₂)
2. Duty Rate ________(%ED)  or Starting Rate ________(Time/Hr)
3. Control Panel Supplied
4. Control step (Balanced ________step)
5. Installation Location, Environmental Conditions or Applied Load
6. Starting Torque ________(%)  or GD² of Motor and Load
7. Speed Control Range
8. Other Requirement

 R = (a^-1 - 0.05) X E₂ /√3 X I₂

 Where:

a=1 Notch Current/Full Load Current
E₂=2ndary Voltage 
I₂=2ndary Current
R=Resistance/Phase

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Tel:82-32-817-4325 Fax:82-32-817-4329