PRD2

When a PRD2 regenerative control is signaled to brake the mechanical load, it causes the motor to act as a generator. The braking energy is sent back into the AC power lines, eliminating the need for heat-producing dynamic braking resistors. Besides simplifying the overall installation, the PRD2 also provides faster braking than is possible with non-regenerative controls.

A PRD2 control is an excellent choice for high duty cycle indexing and reversing; controlling high inertia loads; also hoisting or other applications requiring controlled hold-back torque.

The unique circuit design provides a 4 to 6 Hz velocity and torque loop response in the PRD2. There are no overshoots during acceleration, deceleration or reversing.

The PRD2 interfaces easily with programmable controllers, or directly with process instruments that provide an analog signal output.

Ratings:

1/6 - 2/3 HP

Input:
115 VAC + 10%, 1Ø, 50/60Hz
Output:
0-75 VDC armature, 100/50VDC  field

Ratings:

1/3 - 2 HP

Input:
230 VAC + 10%, 1Ø, 50/60Hz
Output:
0-150 VDC armature, 200/100VDC field

Overload Capacity:
150% for one minute

Acceleration / Deceleration (optional):
Independent adjustment range:
0.07 to 5 seconds
0.15 to 11 seconds
0.30 to 24 seconds

Speed Regulation:
(percent of base speed with 95% load change)
+ 1% with armature feedback
+ 0.1% with tachometer feedback.

Signal Isolation (optional):
0 - + 6 VDC

Tachometer Feedback (optional):
50 VDC per 1000 rpm standard,
other ranges optional..

Frequency Response:
4 - 6 Hz velocity loop
4 - 6 Hz torque loop

Temperature Coefficient of Speed Setting:
Max +0.05% of base rpm per °C

Dimensions (open chassis):
10 1/4" (W) x 7" (H) x 5-1/2" (D) 

Weight:
open chasis: 5 lbs

PRD2 FEATURES:

* Contactorless braking and reversing
* No AC line transformer required 
* External torque limit terminals
* Velocity and torque loop response is 4 to 6 Hz
* Compact, thermally efficient design
* Optional torque programming
* Transient voltage protection
* Optional selectable tach or armature feedback
* Speed and motor torque meter terminals
* Speed potentiometer kit (supplied loose)
* Adjustable acceleration/deceleration ranges (optional)
* Postion control interface including provision for manual/auto switch, manual postion potentiometer and end-of-travel limit switches (optional)
* Torque programmed drive (optional)
* NEMA enclosures with local or remote operator stations (optional)

PRD8

A PRD8 control is suitable for high duty cycle indexing and reversing, controlling high inertial loads, hoisting or other applications requiring controlled hold-back torque. The PRD8 provides control through zero speed crossing. With an optional plug-in interface the PRD8 can be used in high resolution positioning servo applications.

When a PRD8 is signaled to brake the load, it causes the motor to act as a generator. The braking energy is sent into the AC power lines, eliminating the need for heat-producing dynamic braking resistors. Besides simplifying the overall installation, the PRD8 also provides faster braking than is possible with non-regenerative controls.

The unique circuit design provides a 12 Hz velocity and torque loop response in the PRD8. There are no overshoots during acceleration, deceleration or reversing.

The PRD8 interfaces easily with programmable controllers, or directly with process instruments that provide an analog signal output.

Ratings:

½ - 7 ½ HP

Input:230 VAC + 10%, 1Ø, 50/60Hz
Output: 0-180 VDC armature, 
200VDC field (2 amp max.) or 
100VDC field (3 amp max.)

Overload Capacity:
150% for one minute

Acceleration / Deceleration (optional):
Independent adjustment range:
0.07 to 5 seconds
0.15 to 11 seconds
0.30 to 24 seconds

Speed Regulation:
(percent of base speed with 95% load change)

+ 1% with armature feedback
+ 0.1% with tachometer feedback.

Signal Isolation (optional):
0 - + 6 VDC

Tachometer Feedback (optional):
50 VDC per 1000 rpm standard, other ranges optional..

Frequency Response:
12 Hz velocity loop
12 Hz torque loop

Temperature Coefficient of Speed Setting:
Maximum +0.05% change of base rpm per °C

Dimensions (open chassis):
20" (W) x 20" (H) x 8" (D)

Weight:
open chasis: 11 lbs

 

PRD8 Series Model Selection Table
HP	Model
½	PRD8-51
¾	PRD8-76
1	PRD8-101
1 ½	PRD8-150
2	PRD8-200
3	PRD8-300
5	PRD8-500
7 ½	PRD8-750

PRD8 FEATURES:

*Contactorless braking and reversing
* No AC line transformer required
* External torque limit terminals
* Velocity and torque loop response is 4 to 6 Hz
*Compact, thermally efficient design
* Optional torque programming
* Transient voltage protection
* Optional selectable tach or armature feedback
* Speed and motor torque meter terminals
* Speed potentiometer kit (supplied loose)
* Adjustable acceleration/deceleration ranges (optional)
* Postion control interface including provision for manual/auto switch,   manual postion potentiometer and end-of-travel limit switches (optional)
* DC Armature contactor (optional)
* DC Armature/field contactor (optional)
* Torque programmed drive (optional)
* NEMA enclosures with local or remote operator stations (optional)

PRD12B is a high performance regenerative DC speed control. It provides independent adjustment of speed and torque. Speed and torque are always under control, even during acceleration and deceleration. The four quadrant design allows electronic reversing without contactors. Although a DC loop contactor is an optional feature, it serves only as a disconnect between the motor armature and the control output.

The PRD12B uses twelve SCRs arranged in two phase controlled bridges connected back-to-back. This circuit supplies regulated forward or reverse current to the DC motor, independent of motor speed or direction. Because of the twelve SCR configuration, regeneration is accomplished through the armature of the motor, rather than through the field, enabling much quicker drive response. In addition, the 12-SCR control is designed to operate on a 230 or 460 VAC three-phase service, directly from the customer's AC input lines. No input transformers are required.

The PRD12B has cross firing of the SCR forward and reverse bridges providing smooth control through zero-speed crossing.

Ratings:

Input:230 VAC + 10%, 3Ø, 50/60Hz
Output: 0-240 VDC armature, 
150VDC field; 240VDC field optional

Input:460 VAC + 10%, 3Ø, 50/60Hz
Output: 0-500 VDC armature, 
300VDC field