CODES WHICH GOVERN SUCH PRACTICES AS WIRING PROTECTION,
GROUNDING, DISCONNECTS AND OTHER CURRENT PROTECTION.
SEE APPENDIX E FOR MAXIMUM AC LINE SHORT CIRCUIT CAPACITIES
FOR ALL CONTROL CATALOG LISTINGS.
AC Line Impedance
The Baldor Series 23H servo control requires a minimum line impedance of 3%. If the incoming
power line does not have a minimum of 3% impedance, the addition of a line reactor will provide the
needed impedance in most cases. Use the formula below to calculate the size of the line reactor you
must provide. Line reactors are available from Baldor. Note: Continuous input currents for Series 23H
controls provided in Table 2.0 which follows.
L =
(V
L-L
x .03) / (I x 1.732 x 377)
Where:
L
=
minimum line inductance in henrys
V
L-L
=
input voltage measured from line to line
.03
=
desired percentage of impedance
I
=
the continuous input current rating of the control
1.732
=
square root of three
377
=
constant used if the input frequency is 60 Hz. Use 314 if the Input
frequency is 50 Hz.
The controller is self protected from normal AC line transients and surges provided input impedance
from the AC line is at least 3% (voltage drop at the input is 3%minimum when the control draws
rated input current). Additional external protection may be required if high energy surges are present
on the incoming power source. These surges could be caused by sharing a power source with arc
welding equipment, large motors being started across the line, or other industrial equipment
requiring large surge currents. To prevent control damage due to power source disturbances the
following should be considered:
a.
Connect the control on a feeder line with a line impedance of 3% minimum.
b.
Supply power to the control through a 3% minimum impedance line reactor or
transformer.
Line reactors serve several purposes:
1)
minimize voltage spikes from the power line that may cause the control to trip on over-
voltage spikes.
2)
minimize voltage harmonics from the control to the power line.
3)
provide additional short circuit capability at the control.
CAUTION:
DO NOT USE POWER FACTOR CORRECTION CAPACITORS ON THE INPUT
POWER LINES TO THE CONTROL OR DAMAGE TO THE CONTROL MAY
RESULT.
2-2
INSTALLATION
MN723H-10/95 11/28/95 1:07 AM Page 14 (Black plate)
Summary of Contents for 23H Series
Page 11: ...1 8 GENERAL INFORMATION MN723H 10 95 11 28 95 1 07 AM Page 12 Black plate...
Page 83: ...3 30 KEYPAD PROGRAMMING AND OPERATION MN723H 10 95 11 28 95 1 13 AM Page 84 Black plate...
Page 99: ...4 16 DIAGNOSTIC INFO AND TROUBLESHOOTING MN723H 10 95 11 28 95 1 14 AM Page 100 Black plate...
Page 125: ...5 26 APPENDIX G MN723H 10 95 11 28 95 1 21 AM Page 126 Black plate...
Page 126: ...MN723H 10 95 11 28 95 1 21 AM Page 127 Black plate...