srst4000 pages

SHUNT REGULATORS
Shunt Regulators
The SRST Series shunt regulator assemblies are designed
to work with ADVANCED Motion Controls’ four quadrant
regenerative servo drives. During braking most of the
stored mechanical energy is fed back into the power supply,
which charges the output capacitor to a higher voltage. If
the charge reaches the drive’s over-voltage shutdown
point, motor control and braking will cease. To ensure
smooth braking of large inertial loads the use of a shuntregulator is recommended. Verify the need for a shunt
regulator by operating the drive under the worst case
braking condition. If the drive shuts off due to over-voltage
(blinking red LED) a shunt regulator is necessary (typically
during downward move or deceleration).
Model Number
Rated Dissipation
Capability
Clamping
Voltage
SRST50
95 W
50 VDC
SRST70
95 W
70 VDC
SRST80
95 W
80 VDC
SRST90
95 W
90 VDC
SRST175
95 W
175 VDC
SRST185
95 W
185 VDC
SRST380
190 W
380 VDC
SRST400
190 W
400 VDC
SRST50, 70, 80, 90, 175, 185
SRST380, 400
Operation
Features
When the DC Bus reaches the shunt voltage of the shunt
regulator assembly, the voltage comparator unit turns on
the electronic switch, which connects the R1 power resistor
across the DC Bus. This power resistor dissipates the
energy from the DC Bus. After the bus voltage is reduced to
less than the shunt voltage setting the resistor is
disconnected from the bus. A small hysterisis loop allows
time between switching. The SRST assemblies are available
with standard shunt voltages of 50, 70, 80, 90, 175, 185,
380, and 400 volts.
Models SRST50, 70, 80, 90, 175, 185 are designed for
use with servo drives up to 200 volts. These models have a
200 VDC, 1200 μF filter capacitor in them.
Models SRST380 and SRST400 are designed for use with
servo drives up to 400 volts. These models have a 450
VDC, 330 μF filter capacitor in them.
Dissipates Excess Kinetic or Potential Energy to
Prevent Drive Over-Voltage Shut Down
Small Size, Low Cost, Ease of Use
Agency Approvals
US and Canadian safety compliance with
UL 508c, the industrial standard for power
conversion electronics. UL registered under
file number E140173. Note that machine
components compliant with UL are
considered UL registered as opposed to UL
listed, as would be the case for commercial
products.
Compliant with European CE for both the
Class A EMC Directive 2004/108/EC on
Electromagnetic Compatibility (specifically
EN 61000-6-4:2007 and EN 61000-62:2005) and LVD requirements of directive
2006/95/EC (specifically EN 60204-1:2006),
a low voltage directive to protect users from
electrical shock.
Contact factory for custom trip voltages.
RoHS (Reduction of Hazardous
Substances) is intended to prevent
hazardous substances such as lead from
being manufactured in electrical and
electronic equipment.
Release Date:
5/4/2012
Revision:
2.01
ADVANCED Motion Controls · 3805 Calle Tecate, Camarillo, CA, 93012
ph# 805-389-1935 · fx# 805-389-1165· www.a-m-c.com
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