Boston gear Ratiotrol P-3026-BG Owner's manual

Boston Gear®
Ratiotrol®
DC Motor Speed Control
Doc. No. 60881
VEL Series 1/6 – 1 HP
VEH Series 1 – 3 HP
Installation and Op ration
P-3026-BG
An Altra Industrial Motion Company

2P-3026 • Doc. No. 60881 • Boston Gear®Ratiotrol®DC Motor Speed Control
Section
General nformation . . . . . . . . . . . . . . . . . . 3
ntroduction .........................3
General Description . . . . . . . . . . . . . . . . . . 3
Motors .............................3
ModelTypes ........................3
Controller dentification . . . . . . . . . . . . . . . . 3
Ratings ............................4
Operation Conditions . . . . . . . . . . . . . . . . . 4
Performance Characteristics . . . . . . . . . . . . 4
StandardFeatures ...................5
Adjustments.........................5
Options ............................5
Section
nstallation ..........................6
Mounting nstructions . . . . . . . . . . . . . . . . . 6
Wiring nstructions....................6
nitialStartup ........................7
Section
Operation...........................8
PowerOn/Off........................8
Run ...............................8
Stop ...............................8
SpeedControl .......................9
Reversing ..........................9
Jogging ............................9
noperative Controller . . . . . . . . . . . . . . . . . 9
Section V
Maintenance .......................10
General ...........................10
Adjustment nstructions . . . . . . . . . . . . . . . 10
Troubleshooting.....................12
Section V
PartsList ..........................15
Section V
Options ...........................16
Section V
llustrations ........................17
List of llustrations
Figure No. 1 Enclosure Dimensions
VEL/H ...........................17
Figure No.2 Enclosure Dimensions
VEH/H-MR........................18
Figure No.3 Schematic
Run/StopLogic ....................19
Figure No.4 Schematic
DB, Reversing, Jog Options . . . . . . . . . . 20
Figure No.5 nternal View,
Controller ........................21
List of Tables
Table No. 1
ApplicationData ....................4
Table No. 2
Speed Regulation Characteristics . . . . . . . 5
Table No. 4
Dynamic Braking Characteristics. . . . . . . . 8
Table No. 5
Troubleshooting....................12
Table No. 6
Parts List, Controllers . . . . . . . . . . . . . . . 15
Table No. 7
Option Combinations . . . . . . . . . . . . . . . . 16
Table of Contents
General nformation

3
P-3026 • Doc. No. 60881 • Boston Gear®Ratiotrol®DC Motor Speed Control
General nformation
Introduction
This manual contains installation, operation,
and maintenance instructions for the Boston
Ratiotrol VEL and VEH Series single-phase
Adjustable Speed Motor Controllers. A parts list
and illustrations are also included.
General Description
Ratiotrol VEL/H Controllers are general purpose
industrial units which statically rectify single-
phase AC line power to regulated DC for
adjustable speed armature control of DC
motors.
Each controller is furnished in a rugged die cast
aluminum alloy enclosure with a hinged,
gasketed door. A draw latch tightly compresses
the door gasket to exclude contaminants.
Motors
Motors may be shunt wound, stabilized shunt
wound, or permanent magnet DC types. For
maximum efficiency, the motor should be rated
for operation from a NEMA Code K power
source. See Table 1 for motor ratings.
Model Types
Controllers are available in eleven basic
models:
1. VEL16 – VEL100:
115VAC
VEL16 – 1/6 HP
VEL25 – 1/4 HP
VEL33 – 1/3 HP
VEL50 – 1/2 HP
VEL75 – 3/4 HP
VEL100 – 1 HP
2. VEH100 – VEH500:
230VAC
VEH100 – 1 HP
VEH150 – 1-1/2 HP
VEH200 – 2 HP
VEH300 – 3 HP
Basic Units
Standard VEL and VEH Controllers are basic
RUN/STOP units. Other functional features may
be incorporated by adding standardized option
kits, available from stock.
Local Control
Each controller contains an integral operator’s
control panel mounted in the enclosure cover.
This panel contains RUN and STOP
pushbuttons and a MOTOR SPEED
potentiometer. Three predrilled holes with
removable inserts are provided for an optional
JOG SPEED potentiometer, RUN/JOG toggle
switch, FWD/REV toggle switch, and other
optional operator controls.
Remote Control
The remote control station option consists of a
die-cast enclosure with installed terminal board
and blank cover. This allows the controller
operator control panel to be interchanged with
the blank cover for remote operation.
Controller Identification
Each controller contains a data label on the
inside of the enclosure cover. This label
identifies the controller, user connection
terminals and maximum wire size, controller
ratings, operation notes, and applicable options.
Section

4P-3026 • Doc. No. 60881 • Boston Gear®Ratiotrol®DC Motor Speed Control
General nformation
Ratings
1. Horsepower Range 1/6 – 3 HP
2. Power Source 1/6 – 1 HP, 115 VAC, 1-phase, 50 or 60 Hz.
1 – 5 HP, 230VAC, 1-phase, 50 or 60 Hz.
3. 115VAC Unit Output Voltages
Armature 0-90 VDC
Field 50 VDC
4. 230VAC Unit Output Voltages
Armature 0-180 VDC
Field 100 VDC
5. Service Factor 1.0
6. Duty Continuous
7. Overload Capacity (armature circuit) 150% for 1 minute
(Armature Circuit)
Note: nternal load monitor provides automatic shut-down if current exceeds
120% for 80 seconds continuously.
Table I Drive Data – Full Load
perating Conditions
1. Line Voltage Variation — ±10% of rated
2. Line Frequency Variation — ±2 Hertz of rated
3. Ambient Temperature* — 0 to 50 degrees C
(32 to 104 degrees F)
4. Altitude (standard) — 1000 meters
(3300 feet) maximum
* Temperature inside enclosure in which control is mounted
should not exceed 55 degrees C.
Performance Characteristics
1. Speed Range (controlled) – 0 to motor
base speed
2. Speed Range At Rated Torque and
Regulation – 30:1
3. Efficiency (maximum speed)
a. Controller SCR regulator – 97%
b. Complete drive (controller with motor,
typical) – 80%
4. Displacement Power Factor (maximum
speed) – 86%
5. Acceleration (standard) – By current limit
6. Speed Regulation (s Tabl 2) – Regulation
percentages are of motor base speed
under steady-state conditions.
Basic Model AC nput - 1 Phase DC Output Motor - 1750 RPM
HP Volts Amps KVA Armature Field Torque
Volts Amps Volts Amps Lb n Lb Ft
VEL16 1/6 115 3.3 0.4 90 2.2 50 2.0 6 0.50
VEL25 1/4 115 5.0 0.6 90 3.0 50 2.0 9 0.75
VEL33 1/3 115 6.0 0.7 90 3.6 50 2.0 12 1.00
VEL50 1/2 115 9.0 1.1 90 5.6 50 2.0 18 1.50
VEL75 3/4 115 13.0 1.5 90 8.1 50 2.0 27 2.25
VEL100 1 115 15.0 1.7 90 11.4 50 2.0 36 3.00
VEH100 1 230 7.2 1.7 180 5.5 100 2.0 36 3.00
VEH150 1-1/2 230 10.0 2.3 180 8.2 100 2.0 54 4.50
VEH200 2 230 15.0 3.5 180 11.6 100 2.0 72 6.00
VEH300 3 230 16.0 3.7 180 14.4 100 2.0 108 9.00
Section

5
P-3026 • Doc. No. 60881 • Boston Gear®Ratiotrol®DC Motor Speed Control
General nformation
Variable
Regulation Load Line Field Temperature
Method Change Voltage Heating (1)
95% ±10% Cold/Normal ±10ºC
Standard Voltage
Feedback with R
Compensation
2-3% 2% 5-12% 1%
Optional Speed
(tach) Feedback 0.5% 0.5% 0.5% 0.5%
Standard Features
1. Power Conversion --– NEMA Code K
semiconverter power bridge consisting of two
SCR’s, two diodes and a freewheeling diode.
Power bridge is an integrated, encapsulated
component. (S Figur 5, pag 21)
2. Reference Power Supply – +10 VDC
regulated, with respect to common.
3. Feedback – CEMF voltage with adjustable R
compensation.
4. Control Transformer – 24 VAC secondary
isolates all operator controls and magnetic
control logic from the AC power source for
operator protection. (S Transform r T1,
Figur 5, pag 21)
5. Motor Contactor – Provides positive
disconnection of motor armature from the
controller output, and undervoltage
protection. A phase-off circuit ensures that
the contactor does not make or break DC.
(S Figur 5, pag 21)
6. Motor Overload – Positive motor protection
by an electronic nonadjustable current (load)
monitor. This circuit shuts down the drive
when the motor armature current exceeds
120% for 80 seconds. An optional current
(load) monitor (Option Kit Cat. No. 60177) is
available which provides an adjustable trip
range and an adjustable time delay range.
This option provides a relay with one set of
Form C, 2 ampere (120 VAC – 28 UDC)
contacts which can be used to signal audible
or visual alarms, or auxiliary control devices,
e.g., lubrication pumps, fans, valves.
7. AC Line Disconnect – Provided by a single-
pole, magnetic-trip only circuit breaker with a
5000 ampere interruption capacity. (S
Figur 5) An optional two-pole circuit breaker
(Option 30, Kit Cat. No. 60169) is available
which opens both lines of the input supply.
8. Line Transient Protection – Provided by a
metal oxide varistor (MOV) suppressor
across the AC input line. (S RV1 on Figur
5)
9. UL Listed – File E60208
Adjustments
The following adjustment potentiometers are
located on the standard circuit boards in the
controller. (S Figur 5)
1. Maximum Speed – 60 to 100% of motor base
speed
2. Minimum Speed – 0 to 30% of motor
base speed
3. R (load) Compensation – 0 to 100% of
rated load
4. Current Limit – 50 to 150% of full-load torque
ptions
Standardized pre-engineered optional
equipment can be supplied with Controllers at
additional costs. S S ction VI for option
listing.
Section
Table 2 – Speed Regulation Characteristics
(1)Do s Not Apply to P rman nt Magn t Motors.

Mounting Instructions
S Figur s 1 & 2, pag s 17 & 18
1. The enclosure is designed for vertical surface
mounting in a dry location. t should not be used
where a water-tight or weatherproof enclosure
is required.
Never mount the enclosure
immediately beside or above
heat-generating equipment, or directly below
water and steam pipes.
Comply with the following mounting
requirements:
a. Mount the enclosure in a vertical
position, allowing four (4) inches
minimum clearance on all sides, for
maximum cooling efficiency.
b. Fasten the enclosure securely on a level
surface with the mounting tabs provided.
See Figure 1 for enclosure dimensions.
c. Shock and excessive vibration are
detrimental to controller performance and
life. Vibration can cause general
deterioration of connections, and
component damage. Therefore, shock-
mount the controller if it is subjected to
external vibrations.
2. f the motor is to be foot mounted, bolt the
motor to a firm, flat foundation. f the
foundation is not flat, use shims to prevent
strain when tightening the bolts. f the motor
is to be connected directly to a machine, be
sure of correct alignment. Pulleys and
couplings must slip freely onto the motor
shaft.
Never hammer the pulleys,
couplings, or motor shaft, nor
overtighten drive belts or timing chains. Bearing
damage could result.
Wiring Instructions
Refer to the data label inside the enclosure
cover and be sure the input voltage and
frequency to the controller complies with its
rating. A surge suppressor (varistor) protects
the controller from normal line transients and
surges. However, to prevent problems from
high-energy transients and large surges,
observe the following:
1. Place the controller on a feeder line separate
from that supplying large inductive loads.
2. f the input power to the controller comes
directly from a transformer, always switch
power ON and OFF between the transformer
secondary and the controller.
Never make or break power
in the transformer primary.
Transients could be generated which could
damage the controller.
3. f the controller must be fed from an AC
circuit which also supplies highly inductive
loads, additional suppression may be
required to limit transients or surges to 150%
of peak line voltage.
Never use power factor
correction capacitors on the
input line to the controller. These capacitors can
damage the solid-state components.
The wire size of the input power and motor
wiring can be determined from Table 1 and the
controller data label.
1. Do not use wire larger than
#12 AWG. versize or solid
wire, as well as oversize screwdrivers for
electrical connections, can break terminal board
barriers.
2. All wiring must comply with the national and
local electrical codes.
Use the 3/4-14 NPT tapped conduit holes in the
enclosure to facilitate wiring.
All external wiring for low voltage signal
sources, e.g., potentiometers, tachometer
generators, transducers, should be run in
separate conduit from all other wiring. Use
twisted wire (5 to 6 twists per foot) or shielded
cable. Maintain the separation of power and
signal wiring within the enclosure.
Pickup from unwanted
signals can cause erratic
operation and/or controller damage.
6P-3026 • Doc. No. 60881 • Boston Gear®Ratiotrol®DC Motor Speed Control
nstallation
Section
CAUTI N
CAUTI N
CAUTI N
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7
P-3026 • Doc. No. 60881 • Boston Gear®Ratiotrol®DC Motor Speed Control
nstallation
AC Power Connections
Connect the AC input power wires to controller
Terminals L1 and L2 on Terminal Board TB1.
(S Figur 5)
f one of the power wires is a neutral wire
(grounded potential), connect the hot wire (H) to
Terminal L1 and the neutral wire (N) to Terminal
L2. Connect the controller Ground Screw
(GND) to an earth ground according to
applicable electrical codes. Ground Screw
(GND) is located near the bottom of the
controller enclosure. (S Figur 5)
If the neutral wire (Terminal
L2) is not grounded, the
controller remains electrically "hot" when the
AC power N/ FF switch is turned off.
Motor Connections
Check the connection diagram supplied on or
with the motor. f the motor has dual voltage
shunt fields, connect the field terminal straps (or
leads) for low field voltage.
Connect the motor field and armature terminals
(or leads) to controller Terminals F+, F-, A+, and
A-, respectively, on Terminal Board TB1.
Do not ground the motor
wiring. Grounded wiring can
cause controller damage.
Connect the motor thermal guard, if applicable,
to Terminals 2 and 3 on Terminal Board TB2.
Be sure to remove the jumper wire from
Terminals 2 and 3 if a thermal overload is used.
(S Figur 5)
Initial Startup
Before energizing the controller for the first
time, be familiar with any installed options.
See the option selection table on the controller
data label.
The controller has been factory tested and
adjusted with a motor under simulated
operating conditions. Therefore, startup
adjustments should not be needed. However,
the following startup procedure should be
performed for proper operation, system
compatibility, and safety.
1. Be sure all interconnection wiring is correct,
and all wiring terminations are tightened
securely. Wiring errors and accidental
grounds can cause controller and/or
motor damage.
2. For 50 Hertz operation, be sure the 60 Hz
jumper wire is removed (cut out) from the
control board. (S Figur 5)
3. Close and latch the enclosure cover.
4. Turn the MOTOR SPEED potentiometer fully
counterclockwise to zero.
5. f so equipped, place the RUN/JOG switch in
RUN position and the FWD/REV switch in
FWD position.
6. Couple the motor to the machine (load).
7. Turn on the AC input power and the AC
POWER ON/OFF switch.
8. Depress the RUN button, and slowly turn the
MOTOR SPEED potentiometer clockwise
until the motor rotates. f motor rotation is
opposite to that desired, stop the motor with
the STOP button, turn off the AC POWER
ON/OFF switch and the AC input power, and
interchange the motor armature leads.
Never use line switching to
start and stop the motor.
Resulting transients may cause controller
damage.
9. Turn the MOTOR SPEED potentiometer fully
clockwise to 100 and observe motor rotation.
The motor should run at its rated (base)
speed.
10. Turn the MOTOR SPEED potentiometer
fully counterclockwise to zero and depress
the STOP button.
Section
CAUTI N
CAUTI N
WARNING

8P-3026 • Doc. No. 60881 • Boston Gear®Ratiotrol®DC Motor Speed Control
Operation
Power N/ FF
To energize (turn on) the controller, place the
AC POWER ON/OFF switch in ON position.
Conversely, to de-energize (turn off) the
controller, place the switch in OFF position.
The AC POWER ON/OFF switch is a circuit
breaker which not only connects and
disconnects the AC input power, but also
protects the controller and motor from electrical
faults. f the circuit breaker trips, reset it by
turning it OFF, then ON. f the circuit breaker
retrips, an electrical fault is indicated which
must be corrected. See the Troubleshooting
Table in Section V.
1. Continual resetting of the circuit
breaker could damage
the controller.
2. Never use the circuit breaker to start and
stop the motor. Controller damage could
result.
If line terminal L2 is not
grounded, the controller
remains electrically "hot" when the circuit
breaker is turned off.
Run
To start the motor, depress the RUN button, and
the motor will accelerate to the setting of the
MOTOR SPEED potentiometer.
Stop
To stop the motor, depress the STOP button,
and the motor will stop at a rate proportional to
the motor load. f the controller contains
dynamic braking (Option "D", Cat. No. 60159),
the motor will dynamically brake to a rapid stop.
Dynamic braking provides exponential rate
braking of the motor armature, which occurs
when the circuit opens between the controller
and the motor armature, and a Resistor (DB)
connects across the armature. This is
accomplished by a contact, interlocked with the
normal run contact.
When a Stop (dynamic braking) function is
initiated, the motor functions as a DC generator
and feeds its counter EMF through Resistor DB
where it is dissipated as heat. This opposes
motor rotation, thereby stopping the motor.
Resistor DB is rated to provide initial braking
torques as shown in Table 4.
Section
Rated Horsepower
Component Unit 1/6 1/4 1/3 1/2 3/4 1 1-1/2 23
Braking 115V 300 215 170 100 75 60 ———
Torque % 230V —————220 145 105 85
Stops Per 115V 9 65544———
Minute 230V —————4332
Table 4 – Dynamic Braking Characteristics
CAUTI N
WARNING

9
P-3026 • Doc. No. 60881 • Boston Gear®Ratiotrol®DC Motor Speed Control
Operation
High inertia loads may
extend braking time beyond
the wattage rating of the resistor.
Option "D", Cat. No. 60159 also provides an
Antiplug Relay (APR) which picks up
immediately after the motor starts and drops
out immediately before the motor stops. An
APR contact, connected in the run/stop logic,
prevents restarting the motor until the braking
cycle is complete.
Speed Control
Motor speed is directly proportional to the
setting of the MOTOR SPEED potentiometer.
This potentiometer may be adjusted while the
motor runs or may be preset at any position
before the motor is started. The speed range of
the controller is limited only by the limitations of
the motor.
Reversing
To reverse motor rotation on reversing
controllers (Option "R", Kit No. 60160), depress
the STOP button, place the FWD/REV switch in
the opposite position, and depress the RUN
button. The motor will accelerate to the setting
of the MOTOR SPEED potentiometer. Forward
and reverse speeds are identical.
N TE:
The FWD/REV switch contains a center
position interlock, which requires a momentary
relaxation of pressure before the reverse
position can be engaged.
This center position causes a Stop function,
and an antiplug circuit prevents the motor from
being restarted while the motor is braking until
a safe speed for reversing is attained.
Jogging
To jog the motor on controllers with jog
capabilities (Option 9, Kit No. 60166), place the
RUN/JOG switch in JOG position and jog the
motor with the RUN button. Jog is momentary,
causing motor rotation only while the RUN
button is held depressed. Release the RUN
button to stop the motor.
Inoperative Controller
f the motor stops and/or won’t start, check for a
tripped AC POWER ON/OFF switch. f tripped,
reset the switch. f the switch retrips, s th
Troubl shooting Tabl in S ction IV.
f the switch is not tripped, the internal current
monitor may have shutdown the drive. The
standard current monitor will shutdown the
controller and motor if the motor armature
current exceeds 120% of rated for 80 seconds
of continuous operation. To reset the controller,
depress the STOP button, remove the overload,
and depress the RUN button to restart.
Repeated shutdown indicates a continual
overload (mechanical or electrical) which must
be removed. S th Troubl shooting Tabl in
S ction IV.
Section
CAUTI N

1. Controllers contain high
voltage which can cause
electric shock resulting in personal injury
or loss of life.
2. Never clean or repair the controller or
motor with the AC input power on.
3. When the circuit breaker is turned-off,
components within the controller remain
at line potential until the AC input power
is turned off.
General
VEL/H Controllers require very little
maintenance, other than an occasional visual
inspection and, if necessary, external cleaning.
They must be kept dry and reasonably free
from dust, dirt, and debris. No parts require
periodic replacement.
Maintain the motor according to maintenance
instructions supplied by the motor manufacturer.
Visual Inspections
1. Be sure all wires are fastened securely.
2. Check components for damage due to
overheating or breakage. All damaged and/or
faulty components must be replaced for
satisfactory operation.
Adjustment Instructions
All Controllers have been factory tested and
adjusted under load. No adjustments should be
required for normal operation. However, if circuit
boards are replaced, or if factory adjustments
are changed, the following adjustments can be
made. All adjustments must be made in strict
conformance to the instructions given herein. f,
during any step of the adjustment procedure, it
is not possible to attain the stated result, stop
the motor, turn off the AC input power and refer
to the Troubleshooting Table (Tabl 5).
Refer to Figure 4 for the location of the internal
adjustment potentiometers.
Preliminary
1. Be sure the controller and motor are at
operating temperature, usually achieved
within 30 minutes from a cold start.
2. Check the motor shunt field voltage on TB1
Terminals F+ and F-. f rated line voltage is
115 VAC, the shunt field voltage should be
50 VDC, ±5 VDC. f rated line voltage is 230
VAC, the shunt field voltage should be 100
VDC, ±10 VDC.
Minimum Speed
1. Turn the MOTOR SPEED potentiometer fully
counterclockwise.
2. Depress the RUN button, and slowly turn the
M N SPEED potentiometer (R1) clockwise
until the motor starts to turn.
3. Turn M N SPEED potentiometer (R1)
counterclockwise until the motor stops.
4. f desired, minimum speed can be increased
to 30% of motor base speed.
Maximum Speed
1. Depress the RUN button, and turn the
MOTOR SPEED potentiometer fully
clockwise.
2. Turn the MAX SPEED potentiometer (R59)
until the motor runs at rated (base) speed. f
a tachometer is unavailable, connect a DC
voltmeter across the motor armature, and
adjust MAX SPEED potentiometer (R59) until
the voltmeter records rated armature voltage.
3. f desired, maximum speed can be
decreased to 60% of motor base speed.
Do not exceed rated armature
voltage or base speed.
vervoltage and resulting overspeed can
damage the motor.
10 P-3026 • Doc. No. 60881 • Boston Gear®Ratiotrol®DC Motor Speed Control
Maintenance
Section V
WARNING
CAUTI N

IR Compensation
R compensation is factory adjusted and sealed
for 3% maximum speed change with a 95%
load change throughout the motor speed range.
Therefore, readjustment should not normally be
necessary. However, if the following facilities
are available, readjustment can be performed.
To adequately adjust R compensation, an
adjustable load is required that can be applied
and removed while the motor is running. n
addition, a close reading tachometer is needed
to record speed changes. f these facilities are
unavailable, do not readjust R compensation.
f, during this adjustment procedure, motor
speed becomes unstable or oscillates (hunts),
slowly turn R COMP potentiometer (R9)
counterclockwise until the hunting stops.
1. Turn R COMP potentiometer (R9) fully
counterclockwise.
2. Remove the load from the motor and
depress the RUN button.
3. Turn the MOTOR SPEED potentiometer until
the motor runs at the maximum speed of the
desired speed range, normally rated motor
base speed. Record motor speed.
4. Apply load to the motor until it draws rated
armature current. (See Table 1 for motor
current ratings.) Note the speed change.
5. Turn R COMP potentiometer (R9) until the
motor returns to the speed recorded in
Step 3.
6. Remove the load and repeat Step 3.
7. Repeat Steps 4, 5 and 6 until desired speed
regulation is attained.
Current Limit
The current limit prevents excessive armature
current and resulting excessive line current by
limiting armature current at 150% of rated.
Since the current limit is factory adjusted and
sealed, readjustment should not be performed
unless an application requires a lower limit of
armature current, e.g., limiting torque or
accelerating high inertia loads.
1. Turn off the AC input power and connect a
DC ammeter, with a rating of at least twice
rated armature current, in series with the
armature. Observe correct polarity when
connecting the ammeter. (S Tabl 1 for
motor curr nt ratings.)
2. Turn the CURRENT L M T potentiometer
(R12) fully counterclockwise.
3. Connect maximum load to the motor.
4. Turn on the AC input power and the AC
POWER ON/OFF switch.
5. Turn the MOTOR SPEED potentiometer fully
clockwise.
6. Depress the RUN button, and slowly turn
CURRENT L M T potentiometer clockwise
(R12) while the motor is accelerating until
the ammeter records the desired armature
current.
Do not turn potentiometer
(R12) past the factory setting in
the increase direction.
Resulting excessive current could damage the
controller and motor.
To obtain a particular percentage of rated
output torque, set the armature current at a
percentage of rated armature current; e.g., 50%
torque is obtained with 50% rated armature
current.
11
P-3026 • Doc. No. 60881 • Boston Gear®Ratiotrol®DC Motor Speed Control
Maintenance
Section V
CAUTI N

12 P-3026 • Doc. No. 60881 • Boston Gear®Ratiotrol®DC Motor Speed Control
Maintenance
Troubleshooting
Most electrical failures are caused by incorrect
connections, overload, or the accumulation of
dirt, dust, or moisture. Dirt and dust deposits
limit the transfer of heat from the solid-state
components. Moisture, usually caused by either
"wash-down" or condensation, can cause
insulation failures and short circuits. Be sure
the controller is clean and dry before doing
troubleshooting.
Be sure the AC input power
is turned-off before working in
the controller.
f repeated circuit breaker tripping and/or power
bridge failures occur, check the AC input power
for transients (high level spikes) or rapid power
fluctuations.
f a circuit board fails, check all inputs to the
board for proper values before replacing
the board.
Use standard troubleshooting procedures, e.g.,
continuity checks, to detect faults in relay and
switching logic and operator controls.
Section V
Table 5 – Troubleshooting
ndication Possible Cause Corrective Action
1. AC POWER ON/OFF switch Wiring faulty or incorrect Check all external wiring terminating
trips immediately when in the controller. Correct accordingly.
turned-on Circuit, component, or wiring grounded Remove unwanted ground.
Power Bridge BR1 shorted Replace BR1
Power board failure Replace power board.
Control board failure Replace control board.
Shunt field shorted or grounded Repair or replace motor.
2. AC POWER ON/OFF switch Power Bridge BR1 shorted Replace BR1.
trips when motor starts to turn
Motor shorted or grounded Repair or replace motor.
Control board failure causing Replace control board.
SCR’s to turn-on fully
3. AC POWER ON/OFF trips Overload Check shunt field current.
while motor is running nsufficient shunt field current
causes excessive armature current.
f field current is OK, check for
mechanical overload. f the unloaded
motor shaft does not rotate
freely, replace motor bearings. Also
check for shorted armature. Correct
accordingly.
Loose or corroded connection. Check AC POWER ON/OFF switch
Wiring faulty, incorrect or grounded terminals and all terminals,
connections, and wiring
between the line, controller
and motor.
Motor shorted or grounded Repair or replace motor.
SCR and/or diode breaking down Replace BR1.
(intermittently shorting) in Power
Bridge BR1
Control board failure causing SCR Replace control board.
false firing or misfiring
WARNING

13
P-3026 • Doc. No. 60881 • Boston Gear®Ratiotrol®DC Motor Speed Control
Maintenance
Section V
Table 5 – Troubleshooting (con't)
ndication Possible Cause Corrective Action
4. AC POWER ON/OFF switch AC line open Be sure external disconnect
Tripped, but motor won’t switch or circuit breaker is turned-on
run and rated AC power is applied to
controller.
Operator controls or relay logic Repair accordingly.
inoperative
MOTOR SPEED potentiometer failure Replace potentiometer.
Motor failure Repair or replace motor.
Control, input or power board failure Replace faulty board.
5. Minimum speed excessive High line voltage Check for rated line voltage, ±10%,
on controller AC line terminals.
M N SPEED potentiometer See "Adjustment nstructions".
(R1) misadjusted
Power Bridge BR1 shorted Replace BR1.
Control or input board failure Replace faulty board.
6. Motor does not attain top speed Low line voltage Check for rated line voltage, ±10%,
on controller AC line terminals.
Overload Check shunt field current.
nsufficient shunt field current
causes excessive armature current.
f field current is OK, check for
mechanical overload. f unloaded
motor shaft does not rotate freely,
replace motor bearings. Also
check for shorted armature. Correct
accordingly.
MOTOR SPEED potentiometer failure Replace potentiometer.
MAX SPEED potentiometer See "Adjustment nstructions".
(R59) misadjusted
CURRENT L M T potentiometer See "Adjustment nstructions".
(R12) misadjusted
Control or input board failure Replace faulty board.
Power Bridge BR1 failure Replace BR1.
7. Motor runs at fast speed only Power Bridge BR1 failure Replace BR1.
Control board failure Replace faulty board.
Feedback circuit open Check for open Resistance Wire
(R1-R9) and feedback board. Repair
accordingly.
8. Unstable speed AC line voltage oscillating Observe line voltage with voltmeter
oscilloscope. f oscillations occur,
contact electrician or local utility
company.
Oscillating load connected to Correct condition accordingly.
the motor Turning R COMP potentiometer
(R9) counterclockwise may minimize
condition.
Motor failure Check motor brushes, replace if
needed. Repair or replace motor.

14 P-3026 • Doc. No. 60881 • Boston Gear®Ratiotrol®DC Motor Speed Control
Maintenance
Table 5 – Troubleshooting (con't)
ndication Possible Cause Corrective Action
8.Unstable Speed R compensator misadjusted See "Adjustment nstructions".
(Con’t) SCR(s) misfiring or false firing Replace Power Bridge BR1
and/or control board.
9. High, unstable speed, Armature and field connections Check controller-to-motor
low torque interchanged wiring.
Power Bridge BR1 failure Replace BR1.
10. Top speed only 1/2 Power Bridge BR1 failure Replace BR1.
(approximately) of motor base
speed and motor noisy
(possible half-waving) Faulty control board Replace control board.
11. Motor surges when starting Open or faulty K1 Relay contact Replace Relay K1 or the power
board. Contact must close between
starts.
Power Bridge BR1 breaking down Replace BR1.
(shorting intermittently)
Faulty control board Replace control board.
12. Line and armature current Overload Check shunt field current.
excessive nsufficient shunt field current
causes excessive armature
current. f field current is OK,
check for mechanical overload. f
unloaded motor shaft does not
rotate freely, replace motor
bearings. Also check for shorted
armature. Correct accordingly.
13. Shunt field current insufficient Open shunt field winding or wiring Check motor shunt field and
to the shunt field associated circuitry for loose
connection or broken wire.Repair
accordingly.
Power Bridge BR1 failure Replace BR1.
14. Shunt field current excessive Power Bridge BR1 failure Replace BR1.
Shunt field windings shorted Check shunt field current and/or
measure shunt field resistance
and compare with motor data
plate. Repair or replace motor.
15. Motor thermal switch open Ventilation insufficient Free the motor intake and
(if used) exhaust screens from dirt, dust
and debris.
Motor armature drawing Check shunt field current.
excessive current nsufficient shunt field current
causes excessive armature
current. f field current is OK,
check for a mechanical overload.
Correct accordingly. Motor fields
should be connected for low
voltage.
Motor overheating from friction Check for misalignment. Realign
motor.
Shorted motor windings or Repair motor.
faulty bearings
Section V

15
P-3026 • Doc. No. 60881 • Boston Gear®Ratiotrol®DC Motor Speed Control
Parts List
Parts List
VEL-VEH RAT OTROL
Table 6
Dwg Boston Typical Equivalent
Desig Description Part No. Used n Qty Manufacturer Part Number CB1 Circuit Breaker 60237 All 1 Airpax UPG1-1-6-9-303-9 ----- Control Board 60208 All 1 None ----- ----- Power Board - 115V 60209 VEL16-100 1 None ----- ----- Power Board - 230V 60210 VEH100-300 1 None ----- ----- nput Board 60211 All 1 None ----- ----- Feedback Board 60212 All 1 None ----- BR1 Power Bridge - 115V 60229 VEL 16-100 1 nt’l. Rect. P101W BR1 Power Bridge - 230V 60228 VEH100-300 1 nt’l. Rect. P102W ----- Operator’s Panel, Complete 60158 All 1 None -----
Pushbutton only, green 60244 All 1 Alco C251L-5 Pushbutton only, red 60243 All 1 Alco C251D-5 Pushbutton contact block 60242 All 2 Alco SW00100 Pot, Motor Speed 60246 All 1 Allen Bradley 72A1G Pot, Jog Speed 60246 Jog Option No. 9 1 Allen Bradley 72A1G048D5024 Knob, Pot 60245 All 1 Rogan RB672AML
T1 Transformer 60259 All 1 nelco P-1883 APR Relay, Anti-Plug 60263 Jog & Reverse Options 1 P & B R10-E1-Y4-JJ
K1 Relay 60262 All 1 P & B R50-E2-Y2 MF Contactor, Run or Fwd 60261 All 1 P & B KUM11D59 D1-D9 Diode 63717 Power Boards 9 Jedec N5393 RV1 MOV Suppressor - 115V 60877 60209 Power Board 1 G.E. V130LA10A RV1 MOV Suppressor - 230V 60878 60210 Power Board 1 G.E. V250LA15A C1 Capacitor 60274 Power Boards 1 Sprague TE1304 C2, C3 Capacitor 60275 Power Boards 2 Sprague TE1307 DB Resistor, DB 15 ohm 50W 60265 DB Option “D” 1 Dale RH-50 50W 15 ohms ----- Switch, Fwd/Rev 60266 Sel. Switch Rev. Option “R” 1 Cutler-Hammer 7992K10 ----- Switch, Jog/Run 60268 Jog Option No. 9 1 Alco STV205N0 ----- Latch 63817 All 1 Simmons Link-Lock No. 3
----- Pipe Plug, Conduit 63818 All 3 ----- 3/4-14 NPT
Note: Substitution of parts will void UL listing.
Section V

Table 7 – ptions
Any single controller can have one option from each option group A, B, C and D and any or all of the
group E options, except Option No. 36, centerwind torque control, which utilizes both input and feedback
circuitry and thus cannot be used with any input options (Group B). All options are available factory
installed or as kits for field installation.
Option Group Option No. Description
A – Switching Options "D" Dynamic Braking
"R" Reversing, Selector Switch*
MR Reversing, Auto. magnetic**
9 Jog, Selector Switch
B – nput Options 14 Master Override Board
17 Adj. Linear Accel/Decel
22 Tach. Follower
25 Ext. MA Signal – solated
33 Speed Pot solation
35 Follower, Master sol. Ref.
C – Feedback Options 18 Torque-Taper
24 Tach. Feedback
36 Centerwind Torque Control
D – Miscellaneous 31 Load Monitor
32 Full Wave Field Supply
E – “Operator’s Options 6 Remote Operator’s Station
21 10-Turn Speed Pot
27 NEMA 3, 4, 12, & 13 Kit
* Includ s Option D, Dyn. Braking
** Includ s Option D and Option9, Jog
16 P-3026 • Doc. No. 60881 • Boston Gear®Ratiotrol®DC Motor Speed Control
Options
Section V

17
P-3026 • Doc. No. 60881 • Boston Gear®Ratiotrol®DC Motor Speed Control
llustrations
Section V
Max. Control Proj. .65 1.35 Circuit
Breaker
Operator
Panel
Mounting
Slot
Width
.25
8.59
9.34
12.00
1.33
1.20
1.75
6.00
10.55
6.30
.25
9.06
16.81
Conduit
Entrance
3/4-14 N.P. T.
(4) Places
Ratiotrol D.C. Systems
Figure 1
VEL/VEH Series
1/6-3 Horsepower Dimensions

18 P-3026 • Doc. No. 60881 • Boston Gear®Ratiotrol®DC Motor Speed Control
llustrations
Section V
6.30
.65 Max
Control
Proj.
4.25
1.75
1.75
6.00
1.20
Conduit Entrance
3/4-14 N.P. T.
(6) Places
25.00
Approx.
9.34
3.75
Approx.
9.34
1.33
8.59
1.35
(8) Mounting
Slots
.25 Wide
9.06
16.81
10.55
Figure 2
Approximate Weights
VEL Controls 30 Pounds
VEH Controls 32 Pounds
Ratiotrol D.C. Systems
Figure 2
VEL/VEH Series
Auto. Magnetic Reversing Models
1/6-3 Horsepower Dimensions

19
P-3026 • Doc. No. 60881 • Boston Gear®Ratiotrol®DC Motor Speed Control
llustrations
Section V
Ratiotrol D.C. Systems
Figure 3
VEL/VEH Series

20 P-3026 • Doc. No. 60881 • Boston Gear®Ratiotrol®DC Motor Speed Control
llustrations
Section V
Ratiotrol D.C. Systems
Figure 4
VEL-90VDC Arm VEH-180VDC Arm
A-
APR
R12 10K 2W
1
A+
Jumper 115V
Jumper 115V
MR
2
E8
RunStop DB
Rev DB
E7
E6
1
D8
15, 50w
MF
Power Bd
E9
E18
R11 150k 1/2w R10 200k 1/2w
MF
MR
MR
MF
2 2
R1, 042 Each
E5
E4
E15
E14
22 23
E16 E17 100MV @150% Load
24 25
R9
+
9
19 20 21
BR1
+
G2
AC2
AC1
11
8
9
E3
E19 E20
VEL-50VDC Field VEH-100VDC Field
F-
F+
CB1
30A
RV1
L1
L2
115V
230V
115V115V
Blk/Wht
T1
Power Bd
Blk/Red
Blk
Wht
24V 20V 20V
21543
K1
E10
E13
13
E11
E12
12
14 15
D1 D2
D4
D3
22
3
3APR 1
44
K1
A1
66
Fwd
5
5
Rev
2
34
Jog
Run
1
4
Run Stop
27 D9 R15
10
50, 50V
50, 50V
2MR
MF
K1
+
C3
C2
R14
10
D8
D7
D5 R13
2.2k
D6
50V
+
C1 10
16
Motor Spd 5k
17
18
3
3
3
4.7k
Jog Spd
5k
10
16
26
18 28
3 4
2
1Input Bd
Feedback Bd
100 0
Control Bd
J2 P1
13 15 10 14 14 13 15 12
6 22 9 21 5 19 124 2 3
23
25
G1
E1
E2
DB Option
Reversing Option
Jog Option (Separate Pot)
1
1 2
3
Figure 4