Iron Horse GSD7 Series User manual

Page 1IronHorse GSD7 DC Drives User Manual – 1st Ed, Rev C – 10/24/2018
™
GSD7 SerieS DC DriveS USer ManUal
User ManUal nUMber: GsD7_UMP

Page 2 IronHorse GSD7 DC Drives User Manual – 1st Ed, Rev C – 10/24/2018
~WarninG ~
Thank you for purchasing automation equipment from Automationdirect.com®, doing business as
AutomationDirect. We want your new automation equipment to operate safely. Anyone who installs or
uses this equipment should read this publication (and any other relevant publications) before installing or
operating the equipment.
To minimize the risk of potential safety problems, you should follow all applicable local and national codes
that regulate the installation and operation of your equipment. These codes vary from area to area and
usually change with time. It is your responsibility to determine which codes should be followed, and to verify
that the equipment, installation, and operation is in compliance with the latest revision of these codes.
At a minimum, you should follow all applicable sections of the National Fire Code, National Electrical Code,
and the codes of the National Electrical Manufacturer’s Association (NEMA). There may be local regulatory or
government offices that can also help determine which codes and standards are necessary for safe installation
and operation.
Equipment damage or serious injury to personnel can result from the failure to follow all applicable codes and
standards. We do not guarantee the products described in this publication are suitable for your particular
application, nor do we assume any responsibility for your product design, installation, or operation.
Our products are not fault-tolerant and are not designed, manufactured or intended for use or resale as
on-line control equipment in hazardous environments requiring fail-safe performance, such as in the
operation of nuclear facilities, aircraft navigation or communication systems, air traffic control, direct life
support machines, or weapons systems, in which the failure of the product could lead directly to death,
personal injury, or severe physical or environmental damage (“High Risk Activities”). AutomationDirect
specifically disclaims any expressed or implied warranty of fitness for High Risk Activities.
For additional warranty and safety information, see the Terms and Conditions section of our catalog. If you
have any questions concerning the installation or operation of this equipment, or if you need additional
information, please call us at 770-844-4200.
This publication is based on information that was available at the time it was printed. At AutomationDirect
we constantly strive to improve our products and services, so we reserve the right to make changes to the
products and/or publications at any time without notice and without any obligation. This publication may
also discuss features that may not be available in certain revisions of the product.
TraDeMarkS
This publication may contain references to products produced and/or offered by other companies. The
product and company names may be trademarked and are the sole property of their respective owners.
AutomationDirect disclaims any proprietary interest in the marks and names of others.
Copyright © 2013, 2018 Automationdirect.com®Incorporated
All Rights Reserved
No part of this manual shall be copied, reproduced, or transmitted in any way without the prior, written
consent of Automationdirect.com®Incorporated. AutomationDirect retains the exclusive rights to all
information included in this document.

Page 3IronHorse GSD7 DC Drives User Manual – 1st Ed, Rev C – 10/24/2018
Contents
GSD7 Series DC Drives User Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
~WARNING ~. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
Trademarks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
GSD7 DC Drives User Manual Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
IronHorse GSD7 Series DC Drives General Information . . . . . . . . . . . . . . . . . . . . . . . . . .4
Selection and Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
Dimensions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Installation and Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Start-Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Trim Pot Adjustments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
GSD7 DC DriveS USer ManUal OvervieW
overview of this PUbliCation
The IronHorse GSD7 Series DC Drives User Manual describes the installation, configuration, and
methods of operation of the GSD7 Series DC Drives.
All information contained in this manual is intended to be correct. However, information and data
in this manual are subject to change without notice. AutomationDirect (ADC) makes no warranty of
any kind with regard to this information or data. Further, ADC is not responsible for any omissions or
errors or consequential damage caused by the user of the product. ADC reserves the right to make
manufacturing changes which may not be included in this manual.
who shoUlD reaD this User ManUal
This manual contains important information for those who will install, maintain, and/or operate any
of the GSD7 Series DC Drives.
teChniCal sUPPort
By Telephone: [phone] (Mon.–Fri., 9:00 a.m.–6:00 p.m. E.T.)
On the Web: www.automationdirect.com
Our technical support group is glad to work with you in answering your questions. If you cannot
find the solution to your particular application, or, if for any reason you need additional technical
assistance, please call Technical Support at 770-844-4200. We are available weekdays from 9:00 a.m.
to 6:00 p.m. Eastern Time.
We also encourage you to visit our web site where you can find technical and non-technical
information about our products and our company. Visit us at www.automationdirect.com.
sPeCial syMbols
When you see the “notepad” icon in the left-hand margin, the paragraph to its immediate right will
be a special note.
When you see the “exclamation mark” icon in the left-hand margin, the paragraph to its immediate right Will be a
Warning. this information could prevent injury, loss of property, or even death (in extreme cases).

Page 4 IronHorse GSD7 DC Drives User Manual – 1st Ed, Rev C – 10/24/2018
irOnHOrSe GSD7 SerieS DC DriveS General infOrMaTiOn
The GSD7 series reversing speed control DC drive is designed to provide rapid reversing, quick and
precise stopping, or rapid cycling for a wide range of DC motor applications. The GSD7 series drives
utilize zero-speed-detect and solid-state-assisted dynamic braking circuits. These circuits eliminate
contact arcing and failed braking problems. The zero-speed-detect circuit also eliminates the motor
problems associated with plug reversing a motor by not reapplying power to the motor until zero
speed is obtained.
• Designed so that upon a power loss condition to the drive or an E-stop condition, the drive will drop
into a dynamic brake condition to safely and quickly bring the motor to a stop and remain there until
power is reapplied and a run condition is recognized.
• Extremely small package size that fits the industry standard footprint for both vertical and horizontal
mounting patterns.
• Designed for DC Permanent Magnet and Shunt Wound motors.
• Incoming AC voltage is converted to adjustable full wave rectified DC voltage to operate the DC
motor. A full wave field voltage is provided for shunt wound motors also.
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.
stanDarD featUres
• Input voltages 120/240VAC @ 50/60Hz; output 0–90/180VDC.
• Adjustable horsepower settings.
• Barrier terminal blocks.
• Full-wave bridge supply.
• 1% speed regulation with armature voltage feedback.
• Adjustable Minimum speed, Maximum speed, IR Compensation, and Current Limit.
• Line voltage compensation.
• 5kΩ speed potentiometer with leads, dial, and knob included.
• 50:1 speed range.
• Transient voltage protection.
• Inhibit circuit permits start & stop without breaking AC lines.
• Shunt field supply provided.
• On-board dynamic braking resistor.
• Automatic dynamic braking on power loss.
• Capable of plugging (reversing motor armature polarity to rapidly change motor direction while it is
still running).
• Available in open-frame chassis.

Page 5IronHorse GSD7 DC Drives User Manual – 1st Ed, Rev C – 10/24/2018
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.
IR COMP (Speed Regulation) – 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.
ONBOARD DYNAMIC BRAKE RESISTOR – For automatic dynamic braking.
POWER LOSS BRAKE – Upon an E-stop command or a power loss to the drive, the drive will drop into
a dynamic brake condition to safely and quickly bring the motor to a stop and remain stopped until
power is reapplied and a run condition is recognized.

Page 6 IronHorse GSD7 DC Drives User Manual – 1st Ed, Rev C – 10/24/2018
SeleCTiOn anD SpeCifiCaTiOnS
GSD7 Series DC Drives – Selection & Specifications
Model GSD7-120-
1CR3
GSD7-120-
1CR30
GSD7-120-
5CR3
GSD7-120-
10CR30
GSD7-240-
1CR3
GSD7-240-
5CR3
GSD7-240-
10CR30
Package Configuration open frame
Power Quality Form Factor 1.4
Input Voltage (@50/60Hz) 120 VAC ±10% 240 VAC ±10%
Output Voltage 0–90 VDC 0–180 VDC
Shunt Field Voltage 100 VDC (1A max) 200 VDC (1A max)
Motor Rating (hp) 1/15 – 1/8 1/8 – 1/2 1/8 – 1 1/25 – 1/4 1/4 – 1 1/4 – 2
Output Current
(continuous)
500mA–1.2A
(DC)
500mA–5.5A
(DC)
500mA–10A
(DC)
500mA–1.2A
(DC)
500mA–5.5A
(DC)
500mA–10A
(DC)
Current Overload Capacity 200% for 60s
Current Limit (adjustable) 0.3–3A (DC) 1–18A (DC) 0.3–3A (DC) 1–18A (DC)
Cycling Rate (cycles/min) 3 30 3 30 3 3 30
Transient Protection Metal Oxide Varistor (MOV)
I.R. Compensation adjustable
Speed Adjustment 5kΩ 0.5W potentiometer or 0–10VDC isolated input signal
Speed Range 50:1
Speed Regulation ±1% of base speed
Maximum Speed adjustable from 60% to 110% of base speed
Minimum Speed linear ramp 0–30% of adjustable maximum speed
Acceleration 0.5 seconds
Deceleration 0.5 seconds
Dynamic Braking yes
Plugging Capability ** yes
Electrical Connections barrier-type terminal blocks; 22–14 AWG
External Fusing Required Bussman ABC or Littelfuse 314 series ceramic fuses or equivalent
Refer to “Installation and Wiring” section for details.
Operating Temperature -10 to 45 °C [14 to 113 °F]
Thermal Protection current limiting
Mounting Orientation can be mounted in any orientation
Corrosive Gases NOT compatible with any corrosive gases
Weight 1.1 lb
[490g]
3.3 lb
[1497g]
1.1 lb
[490g]
3.3 lb
[1497g]
1.1 lb
[490g] 1.1 lb [490g 3.3 lb [1497g]
Agency Approvals CULUS Listed (E333109), RoHS
Optional Accessories *
Replacement
Potentiometer GSDA-5K
Digital Potentiometer GSDA-DP
* For accessories details, please visit www.AutomationDirect.com.
** Plugging is a method of rapidly changing motor direction by reversing motor armature polarity, while the motor is still
running.

Page 7IronHorse GSD7 DC Drives User Manual – 1st Ed, Rev C – 10/24/2018
DiMenSiOnS
( DiMensions = in [mm] )
GsD7-xxx-xCr3 GsD7-xxx-xCr30
sPeeD Pot – GsD7-xxx-xCr3 sPeeD Pot – GsD7-xxx-xCr30

Page 8 IronHorse GSD7 DC Drives User Manual – 1st Ed, Rev C – 10/24/2018
inSTallaTiOn anD WirinG
warninGs anD notes
Install open-frame drives in an enclosure with a volume at least three times the volume of the open-
frame drive.
Do not mount GSD7-xxx-xCRxx DC drive where ambient temperature is outside the range of -10 to 45
°C (14 to 113 °F).
Size all wires that carry armature or line currents as specified by applicable national, state, and/or
local codes. All other wires may be 18AWG or smaller as permitted by the codes.
Separate control wires from the armature and AC lines when routed in conduit or wire trays.
caution!! turn poWer off While making Wiring connections.
improper installation or operation of this dc drive may cause injury to personnel or drive failure. the drive
must be installed in accordance With local, state, and national safety codes. make certain that the poWer supply
is disconnected before attempting to service or remove any components!!! ifthe poWer disconnect point is out of
sight, lock it in disconnected position and tag it to prevent unexpected application of poWer. only aqualified
electrician or service personnel should perform any electrical troubleshooting or maintenance. atno time
should circuit continuity be checked by shorting terminals With ascreWdriver or other metal device.
before attempting to Wire the dc drive, make sure all poWer is disconnected. recheck code designation to
assure proper voltage is present for the dc drive. carefully select proper Wire size for current and voltage
drop. limit the voltage drop through the Wiring to 5% of the line voltage at full load
caution!! donot attempt to perform ahi-pot test across the ac lines With the dc drive in the circuit. this
Will result in immediate or long-term damage to the drive.
1) ensure that the gsd7 drive chassis is properly grounded.
2) the inputs to the speed pot terminals (p1-6, p1-7, p1-8) must not be grounded. serious damage may result.
fUsinG
External customer-supplied circuit protection is required for all hot AC lines connected to the GSD7
power input terminals AC1/L and AC2/N (P4-1 & P4-2).
Recommended fuse types are Bussman ABC or Littelfuse 314 or equivalent.
(AutomationDirect sells ABC series fuses.)
Fuse Selection *
GSD7-xxx-xxCRxx
Motor HP Fuse @ 120 VAC Input Fuse @ 240 VAC Input
1/50 2A –
1/20 2A 1A
1/8 3A 2A
1/4 4A 3A
1/3 6A 3A
1/2 8A 4A
3/4 12A 6A
1.0 15A 8A
1.5 – 12A
2.0 – 15A
* Select fuse type Bussman ABC or Littelfuse 314 series or equivalent.
wirinG terMinals
GSD7 Wiring Terminals
Type Wire Range Tightening Torque
barrier-type terminal blocks 22–14 AWG 9.0 lb·in [1.0 N·m]

Page 9IronHorse GSD7 DC Drives User Manual – 1st Ed, Rev C – 10/24/2018
installation anD wirinG (ContinUeD)
wirinG terMinal fUnCtions
GSD7 Series DC Drives – Terminal Strip Functions
CAUTION: BE SURE DRIVE HOUSING IS PROPERLY GROUNDED!
Number Purpose
P4 – Upper Terminal Block Connections
P4-1 (AC1 / L) – For AC systems with a grounded neutral line, connect the Hot (ungrounded) side of your AC line to
this terminal. For systems with two Hot AC lines, connect either of the Hot AC lines to this terminal.
P4-2 (AC2 / N) – For AC systems with a grounded neutral line, connect the Neutral (grounded) side of your AC line
to this terminal. For systems with two Hot AC lines, connect either of the Hot AC lines to this terminal.
P4-3 (A1) – For clockwise rotation of your motor in the Fwd Direction, connect the Plus (+) Armature wire of the
motor to this terminal.
P4-4 (A2) – For counter-clockwise rotation of your motor in the Rev direction, connect the Minus (-) Armature wire
of the motor to this terminal.
P4-5
(REV) – This is the reverse direction input terminal. When connected to the COM terminal, the drive will
release its brake circuit and accelerate to its set point in the reverse direction. When the connection to the
COM terminal is opened, the drive will brake to zero speed. The connection to the COM terminal can be
made via a mechanical switch, a relay contact, or an ungrounded solid-state open-collector type switch.
Switching requirements are 5VDC at less than 1mA.
P4-6
(FWD) – This is the forward direction input terminal. When connected to the COM terminal, the drive will
release its brake circuit and accelerate to its set point in the forward direction. When the connection to
the COM terminal is opened, the drive will brake to zero speed. The connection to the COM terminal can
be made via a mechanical switch, a relay contact, or an ungrounded solid-state open-collector type switch.
Switching requirements are 5VDC at less than 1mA.
P4-7 (COM) – This is the common terminal for the forward and reverse speed/dynamic brake commands.
This terminal should not be grounded or tied to any other terminal.
P1 – Lower Terminal Block Connections
P1-4
(-A/-F) – DO NOT use for Permanent Magnet Motor. This supplies -Field voltage for a SHUNT WOUND
MOTOR. For motors with dual voltage field (i.e. 50/100V or 100/200V), make sure highest value is connected.
Note: When connecting to this terminal, you will need to use a fork or ring connector placed directly under the
screw head.
P1-5 (+F) – DO NOT use for Permanent Magnet Motor. This supplies +Field voltage for a SHUNT WOUND MOTOR.
For motors with dual voltage field (i.e. 50/100V or 100/200V), make sure highest value is connected.
P1-6
(Speed pot Hi) – Connects to high side (white wire) of Speed pot (CW end). This is an internal +12VDC. For
start-stop applications, the connection between this terminal and Speed pot HI can be opened and closed by
a SPST switch. INPUT MUST NOT BE GROUNDED!
P1-7 (Speed pot Wiper) – Connects to wiper (red wire) of Speed pot (center lead). For Voltage-Follower
applications, this INPUT MUST NOT BE GREATER THAN +12V MAXIMUM AND MUST NOT BE GROUNDED!
P1-8
(Speed pot Lo) – Connects to Low side (orange wire) of 5kΩ Speed pot (CCW end). This input is raised and
lowered by the MIN trim pot (5kΩ). Electronic speed input (voltage follower) may be referenced to Speed pot
LO if the MIN trim pot adjustments are to be active. Otherwise, inputs may be referenced to -ARM, which will
bypass the MIN trim pot. INPUT MUST NOT BE GROUNDED!
ensure that the gsd7 control housing is properly grounded.
for applications using analog references other than speed pots (0 to 10v signals), the input connection to the
lo, Wiper, and hi terminals (p1-6, p1-7, and p1-8 respectively) must not be grounded! the gsd7 drive
may be damaged as the result of agrounded input!
sPeeD Pot MoUntinG
CUSTOMER’S
MOUNTING BRACKET
DIALPLATE
(2-inch dia)
SPEEDPOT
KNOB
HEX NUT
LOCK
WASHER
SPEEDPOT

Page 10 IronHorse GSD7 DC Drives User Manual – 1st Ed, Rev C – 10/24/2018
installation anD wirinG (ContinUeD)
wirinG DiaGraMs
GsD7-xxx-xxxxx basiC wirinG DiaGraM
SPEEDPOT
LO
W
HI
SPDT
MOTOR
LO
W
HI
COM
FWD
REV
A2
A1
L
~
N
~
P4
P1
-7
-6
-5
-4
-3
-2
-1
-6
-7
-8
VAC INPUT
VAC INPUT
P1 is underneath P4
P1-4 = -F; P1-5 = +F
For Field Winding of shunt motor;
no connection for permanent magnet motor.
-6
-7
-8
For Speedpot Input:
For 0–10V Analog Signal Input: P1
+10V Analog Signal
0V Analog Common
GsD7-xxx-xxxxx isolation of follower siGnals GsD7-xxx-xxxxx inhibit oPeration
P1
8
7
6
GSD7-xxx-xxxxx
FC-33 (or equivalent)
Isolated Signal
Conditioner
V
+
pot low
pot wiper SPEEDPOT
WIPER
LO
HI
P1
8
7
6
GSD7-xxx-xxxxx
SPST
GsD7-xxx-xxxxx two-sPeeD oPeration
HI
LO
W
LO
HI
W
DPDT SWITCH
(2) 5kΩ Speedpots
P1
8
7
6
GSD7-xxx-xxxxx
(2) 10kΩ Speedpots
P1
8
7
6
LO
HI
W
LO
HI
W
SPDT
GSD7-xxx-xxxxx

Page 11IronHorse GSD7 DC Drives User Manual – 1st Ed, Rev C – 10/24/2018
STarT-Up
all Power MUst be off before ProCeeDinG.
1) Recheck all wiring. Accidental grounds, loose or pinched wires on armature or speed pot wires may
damage the DC drive when power is applied.
2) Check to see that the incoming power is of the correct voltage.
3) Turn the speed pot to zero (fully CCW).
4) Turn power on, close contact from COM (P4-7) to either FWD (P4-6) or REV (P4-5), and advance the
speed pot while observing motor direction of rotation.
Power must be turned off again before step 5 can be accomplished!
5) If the motor rotation is incorrect, turn power off at external disconnect, and reverse the A1 and A2
(P4-3 & P4-4) motor armature connections.
6) Check for satisfactory operation throughout the speed range.
7) If operation is satisfactory, no readjustments are needed.
8) If instability or surging is observed, or if minimum and maximum speed settings need further
adjustments, then refer to the “Trim pot Adjustments” section.”
9) For other problems, consult the “Troubleshooting” section.
TriM pOT aDjUSTMenTS
If the system is unstable after the previous Start-Up procedure, then adjust the trim pots as follows.
These adjustments are maintained, and periodic readjustments are not normally needed. However,
readjustments could be needed if the drive is operated beyond ±10% of the rated line voltage.
GSD7-xxx-xxxxx Trim pot Adjustment
Trim pot Function Adjustment
Max
Sets maximum motor
speed when speed pot is
set at maximum (fully CW
rotation). CW rotation of
MAX trim pot increases
maximum motor speed.
1) TURN DRIVE POWER OFF!!
2) Connect a DC Voltmeter across A1 and A2.
NOTE: Meter must not be grounded!!
3) Set meter voltage range if needed: (90 VDC for 120 VAC; 180VDC for 240
VAC).
4) Turn power ON. Select a direction and set Speed pot at100%.
5) Adjust the MAX trim pot to rated motor armature voltage as shown on
meter. NOTE: A tachometer or strobe may be used in lieu of a meter. Follow
above steps, except adjust MAX trim pot to rated motor base speed indicated
by tachometer or strobe.
Min
Sets minimum motor speed
when speed pot is set at
zero. CW rotation will
increase minimum motor
speed.
1) Select a direction and set Speed pot to zero (fully CCW).
2) Rotate MIN trim pot CW until motor starts to rotate.
3) Slowly rotate MIN trim pot CCW until motor stops. NOTE: If motor rotation
is desired, rotate MIN trim pot CW until desired MIN speed is reached
IR Comp
Provides a means of
improving motor speed
regulation. If a slowdown
due to load change is of no
concern, rotate this trim pot
fully CCW.
1) Select a direction and set Speed pot at 50%.
2) Observe motor speed at no load condition.
3) Apply full load to motor.
4) Turn IR COMP trim pot CW until you obtain the same motor speed as the no
load condition.
Cur Lim
Limits DC motor armature
current (torque) to prevent
damage to the motor or
drive. The current limit
is set for the rated motor
current. CW rotation of
this trim pot increases the
armature current (or torque
produced).
1) TURN DRIVE POWER OFF!
2) Connect a DC ammeter between A1 on motor and A1 on the control. This is
in series with the motor. NOTE: Meter must not be grounded!!
3) Turn power ON.
4) Select a direction and set Speed pot at the 50% position.
5) Apply friction braking to motor shaft until motor stalls.
6) With motor stalled, set current at 125% of rated motor armature current by
adjusting CUR LIM trim pot.

Page 12 IronHorse GSD7 DC Drives User Manual – 1st Ed, Rev C – 10/24/2018
TrOUbleSHOOTinG
If a newly installed DC Drive will not operate, it is likely that a terminal connection is loose. Check the
terminal connections and ensure that they are secure and correct. If the drive is still inoperative, refer
to the Troubleshooting Table.
Troubleshooting
Problem Possible Cause(s) Corrective Action
Motor doesn’t run
1) Blown fuse or circuit breaker
2) Incorrect or no power
3) Speed pot set at zero
4) Worn motor brushes
1) Replace fuse or reset breaker
2) Install proper power service
3) Rotate Speed pot CW to start
4) Replace motor brushes
Armature output
voltage cannot be
adjusted; output is a
constant DC level
1) No motor or load connected
2) Speed pot low connection open
1) Ensure that motor or load is connected to
armature terminals
2) Ensure that Speed pot Low wire is connected
Motor stalls, or runs
very slowly with speed
control set fully CW
1) Low voltage
2) Overload condition
3) Worn motor brushes
4) Max speed set incorrectly
1) Ensure that VAC is above 100 VAC for 120V
systems and above 200V for 240V systems
2) Reduce load or increase motor size or Current
Limit setting
3) Replace brushes
4) Consult “Trim pot Adjustments” section
Motor “hunts”
1) Motor current less than 150 mA
2) Too much IR Comp
3) Motor is in Current Limit
4) Max trim pot set too high
5) Motor speed is above rated speed
1) Motor current must be greater than 150 mA (DC)
2) Consult “Trim pot Adjustments” section
3) Consult “Trim pot Adjustments” section
4) Consult “Trim pot Adjustments” section
5) Reduce speed
Repeated fuse blowing
1) Low voltage
2) Overload condition
3) Worn motor brushes
4) Defective motor bearings
5) Defective electrical components
1) Ensure that VAC is above 100 VAC for 120V
systems and above 200V for 240V systems
2) Reduce load
3) Replace brushes
4) Replace bearings or motor
5) Contact AutomationDirect “Product Returns” for
replacement

Page 13IronHorse GSD7 DC Drives User Manual – 1st Ed, Rev C – 10/24/2018
BLANK
PAG E

Page 14 IronHorse GSD7 DC Drives User Manual – 1st Ed, Rev C – 10/24/2018
BLANK
PAG E

Page 15IronHorse GSD7 DC Drives User Manual – 1st Ed, Rev C – 10/24/2018
BLANK
PAG E

Page 16 IronHorse GSD7 DC Drives User Manual – 1st Ed, Rev C – 10/24/2018
Literature Number: LT140
Drawing Number: A-5-3905D