4
P-3026 • Doc. No. 60881 • Boston Gear
®
Ratiotrol
®
DC Motor Speed Control
General Information
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: Internal load monitor provides automatic shut-down if current exceeds
120% for 80 seconds continuously.
Table I Drive Data – Full Load
Operating 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 (
see Table 2
) – Regulation
percentages are of motor base speed
under steady-state conditions.
Basic Model
AC Input - 1 Phase
DC Output
Motor - 1750 RPM
HP
Volts
Amps
KVA
Armature
Field
Torque
Volts
Amps
Volts Amps
Lb In
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 I