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IronHorse GSD4A / GSD4 DC Drives User Manual – 2nd Ed. Rev. A – 10/14/2019
IronHorse GSD4A Series DC Drives General Information
IronHorse GSD4A DC drives are designed to control DC Permanent Magnet, Shunt Wound, and some
Universal (AC/DC) motors. Incoming AC voltage is converted to adjustable full-wave rectified DC
voltage to operate the DC motor. Also, a full-wave field voltage is provided for shunt wound motors.
Carefully check the DC Drive for shipping damage. Report any damage to the
carrier immediately. Do not attempt to operate the drive if visible damage
is evident to either the circuit or to the electronic components.
GSD4A Standard Features
• Input voltages 120/240VAC, jumper selectable @ 50/60 Hz; output, jumper selectable, 120VAC = 90VDC,
240VAC = 90 or 180VDC.
• Adjustable horsepower settings.
• Barrier terminal strip.
• Full-wave bridge supply.
• 1% speed regulation with armature voltage feedback; ±1/2% with tachometer feedback.
• Adjustable Minimum speed, Maximum speed, IR Compensation, Current Limit, Acceleration & Deceleration
(enclosed models), Inhibit Function.
• Line voltage compensation.
•
5kΩ speed potentiometer with leads, dial, and knob included.
• 50:1 speed range.
• Transient voltage protection.
• Voltage following mode or DC tachometer follower by supplying ungrounded 0–12VDC analog input signal.*
• DC tachometer feedback (6V at base speed).
• Inhibit circuit permits start & stop without breaking AC lines.
• Shunt field supply provided.
* Voltage following and DC tach feedback require the GSDA-AI-V4A analog option card.
GSD4A Control Features
MINIMUM SPEED – Allows adjustment of the motor speed when the speed pot is set at minimum
(CCW). This permits the user to eliminate “Deadband” on the main speed control, permitting zero
calibration. Clockwise rotation of “MIN” trim pot increases speed.
MAX SPEED (Maximum Speed) – Allows adjustment of the motor speed when the speed pot is set at
maximum (CW). This permits the user to eliminate the top end “Deadband”, which will provide full
speed at maximum rotation. Rotation of the “MAX” trim pot in the clockwise direction increases the
maximum motor speed.
I.R. COMP (Speed Regulation) – This allows for adjustment of the circuitry that controls the speed
regulation of the motor. The circuitry controls armature speed by changing the armature voltage to
compensate for increased or decreased motor loading. Clockwise rotation of the “IR COMP” trim pot
will increase compensation.
CUR. LIM. (Current Limit) – Provides protection from excessive armature current by limiting the
maximum armature current the drive can provide. This enables adjustment of the maximum torque the
motor can deliver. Torque adjustment (Cur. Lim.) is preset at 125% of rated motor torque (current) based
on horsepower. Clockwise rotation of the “CUR. LIM.” trim pot increases the torque (current) the drive
will provide.
