MSC38A Series - Eight Channel Master Speed Control
This is a master speed control unit capable of operating multiple speed controls from
a single master potentiometer or any grounded or ungrounded DC voltage or current*
signal, field selectable range of 0-5 through 0-25VDC or 0-25 through 0-200VDC.
STANDARD FEATURES
➯ 120 VAC ±10%, 50/60 Hertz line source.
➯ Eight (3-wire) output channels - each optically isolated.
➯ MSC38A Series may be cascaded to operate more than
➯
➯
➯
➯
➯
➯
➯
➯
eight drives.
Master command input circuit electrically isolated from AC.
Rapid response time.
European type terminal connectors permit 14-24 AWG sizes.
Supply voltage of driven unit is 5-25VDC maximum.
5KW speed potentiometer with leads, dial, and knob for remote mounting included.
Interfaces with Dart 125, 250, or 500 Series controls or most
other manufacturers drives.
Outputs are controlled via a 5KW Master Pot, a field selectable
DC voltage signal (0-5 through 0-25VDC or 0-25 through
0-200VDC), or a 4-20mA current source*.
Each output is capable of driving input impedances as low
as 500W.
MOUNTING
CONFIGURATIONS
NUT
MSC SERIES
PC BOARD
STANDOFF
CUSTOMER
PANEL
SCREW
Conventional mounting (female)
SCREW
MSC SERIES
PC BOARD
* Consult factory for "current source" applications.
STANDOFF
MSC38A HOOK-UP FOR DIRECT OPERATION
CUSTOMER
PANEL
For 0-5VDC through 0-25VDC,
connect P3-1 to P3-2;
For 0-25VDC through 0-200VDC,
connect P3-2 to P3-3
NUT
Master
Speedpot
Conventional mounting (male)
Min
Trimpot
-3 -2 -1
AC1
AC2
Cascade Out
Cascade In
Low
Output to
Control # 1 Wiper
High
Low
Output to
Control # 2 Wiper
High
Low
Output to
Control # 3 Wiper
High
Low
Output to
Control # 4 Wiper
High
High
Wiper
Low
Gain
Trimpot
P1
SCREW
P3
Common
High
Wiper
Low
High
Output to
Wiper Control # 8
Low
High
Output to
Wiper Control # 7
Low
High
Output to
Wiper Control # 6
Low
High
Output to
Wiper Control # 5
Low
P2
MSC SERIES
PC BOARD
STANDOFF
6-32 TAPPED
CUSTOMER
PANEL
For mounting on customer panel with
inaccessible backside, panel holes can be
drilled and tapped to 6-32 and the standoffs
screwed directly into the panel.
Optional DC
Voltage Source
(can be used in place
of Master Speedpot)
TITLE:
MSC38A HOOK-UP & MOUNTING
DIMENSIONS (LT47) - 1 of 2
DWG.
DATE:
7-26-95
REV.
DATE:
DWG. NO.
7-2-02
A-1-2531C
CONTROL DIMENSIONS
English
Width
Height
Length
Weight
3.129"
2.128"
5.403"
7.36 oz.
Metric
7.948 cm.
5.405 cm.
13.724 cm.
208.3 gm.
INPUT HOOK-UP FOR RATIO OPERATION
MOUNTING DIMENSIONS
4.990"
RATIO
CONTROL
FROM
MSC
10K- 250K
OHM
increas
LOW
CONTROL UNIT
(ie. 500, 250, 125 SERIES)
e
SPEEDPOT LO
SPEEDPOT WIPER
SPEEDPOT HI
+ ARMATURE
- ARMATURE
+ FIELD
- FIELD
SPARE
SPARE
AC INPUT
AC INPUT
approx.
5K
WIPER
HIGH
Total height of control
(including standoffs) is
2.128"
2.750"
1. Add (approx.) 5K Resistor from
Lo to Hi of controls being driven.
2. Add ratio pot to controls needing
ratio control.
3. Set min on MSC to full ccw.
4. Using the min trimpot on the
controls being driven, set min speed
to deadband.
5. Set min trimpot on MSC to
deadband.
OPERATING CONDITIONS
Temperature ................................................................................. -10° to +45° C. (+15° to 113° F.)
AC Input Voltage ..................................................................... 120VAC ±10% Rated Line Voltage
Input Frequency ......................................................................................................... 50/60 Hertz
Output Voltage ........................................................................ 0-5 through 0-25VDC each channel
Output Current ................................................................................................ 10 mA per channel
MSC38A SET-UP PROCEDURE
1. Once the hook-up has been completed, select the proper voltage range on P3. Use lower speed
range (connect P3-1 to P3-2) if using the Master Speedpot.
2. Preset Gain and Min trimpots on the MSC38A to full CCW (counter clockwise). Set Master Speedpot fully CCW or DC voltage signal to 0 VDC.
3. Preset Max and Min trimpots on all speed controls fully CCW.
4. Apply power to MSC38A and controllers.
5. Set Master Speedpot fully CW or DC voltage signal to maximum setting.
6. Increase Gain Trimpot setting until no further increase in speed controller output occurs.
7. Adjust Max trimpot on each speed control to the desired output setting.
8. Set Master Speedpot fully CCW or DC voltage signal back to 0 VDC.
9. Adjust Min trimpot of MSC38A CW until an output from the speed control occurs, then back off
(CCW) until 0 volts is achieved on speed controller output.
10 Adjust Min trimpot of each speed control to the desired minimum speed setting if something
other than zero volts is desired.
CASCADE HOOK-UP FOR BASIC CONTROLS
For more than 8
outputs using a single
Master Speedpot,
controls can be
cascaded together via
the cascade and
common terminals as
shown here.
A-1-2531C
(LT47) 2 of 2
Master
Speedpot
Common
Common
MSC # 1
Cascade
Out
MSC # 2
Cascade
In
Common
MSC # 3
Cascade
In