Hubbell Industrial Controls, Inc.
S2MC Compact Primary Thyristor Controller 4922C
For Hoists Without Mechanical Or Eddy Current Brakes
Catalog 4922C • May 1993
General
The Type 4922C S2MC primary thyristor static
reversing controller system provides speed-regulated control of hoist with wound rotor motors and without load
brakes. The Type 4922C system includes the controller
and for separate mounting the Type 5410 tachometer/overspeed switch assembly and Type 3000 secondary
resistor.
The operator control is a Type 4216 stepless mill
master switch. Type 4211 stepless mini master switch or
Type 2015/6/7 stepless pendant pushbutton station. Full
range of motor speed from minimum to maximum is adjusted by the stepless operator. Hoisting speed, with or
without load, is closely controlled by varying the motor primary voltage with thyristors. No-load lowering speed is
handled in the same manner. Lowering speed of an overhauling load at subsynchronous speeds is controlled via
counter-torque control.
4922C controllers are available from 10 to 250 HP
at 460/3/60 VAC.
Operation
Hoisting: When the hoisting direction is selected,
the M contactor closes and hoisting torque is produced by
the motor when selected primary thyristor modules begin
conduction. The amount of thyristor modules begin conduction. The amount of thyristor conduction and hence,
motor hoisting torque, is determined by the master switch
speed reference signal and the tachometer speed feedback
signal. In this manner, stepless adjustable speed control is
obtained for hoisting.
Lowering: When the lowering direction is selected, the M contactor closes and the selected primary
thyristor modules begin conduction.
If the hook is empty or lightly loaded, the controller
will maintain the motor in a stepless speed regulated "driving lower" condition.
If the load overhauls the motor, the controller will
turn off (2) of the thyristor modules and turn on the other (2)
thyristor modules. This transition converts the motor operation from a driving lower condition to a counter-torque
condition with hoisting torque controlling the descending
overhauling load in a controlled stepless manner.
As full speed is reached, the controller reverts
back to a drive down mode and the motor is placed into
regeneration. When leaving the regenerative lowering
mode, the controller reverts back to counter-torque lowering.
Features
The Type 4922C standard controller includes the
following major components/features:
S2MC Compact Variable Speed Control As-
sembly consisting of (1) regulator PC board and (2) firing
circuit board. All adjustments, potentiometers, and test
points for setup and fine-tuning plus status lights are frontpanel-mounted and clearly identified. Simple test setup
readings require use only of a VOM meter.
Five (5) conservatively rated Type 5410 Full
Wave Thyristor Power Modules with MOV transient voltage protection and snubbing circuits to limit rate of voltage
rise. Thyristor modules for 40HP/460 volt and under are
mounted with the S
bly. Over 40HP the thyristor modules are separate mount
within the controller enclosure.
the tachometer feedback signal and shuts down the controller in the event of an open tachometer signal.
controller features a three-pole main knife switch. NEMA
rated mainline contactor, (3) Inverse time trip overload relays, fused control knife switch, 120 volt control transformer, low voltage relay and a shunt brake relay.
2
MC Tachometer Continuity Module monitors
S
In addition to the S
2
MC Compact Speed Regulator Assem-
2
MC modules the Type 4922C
Optional Features
Full Speed Contactor: The 4945C hoist system
requires a secondary slip resistor to provide optimum
torque at reduced speeds, but results in a 20% slip at full
load/full speed. The full speed contactor shorts out this
resistor at high speed and allows the motor to obtain its
maximum rated base speed.
Extended Slow Speed Operation: This option
allows the hoist to operate at reduced speeds for an extended period of time. Recommended for die handling
cranes and turbine handling cranes.
Five Step Reference Board: This option allows
the controller to operate from a standard 5 step sequential
master switch or pendant. Each step can be independently
set for a fixed speed.
Multi-panel Construction: This option provides
two or more controllers to be mounted in a common enclosure and interwired with a mainline contactor panel.
Other standard modifications and options are
available. Consult factory for assistance.
Page 1 of 2
Hubbell Industrial Controls, Inc.
2
S
MC Compact Secondary Thyristor Controller 4922C
For Hoists with Eddy Current Brakes
Catalog 4922C.a • May 1993
Block Diagram
Input Power
Horsepower Range
Speed Range
Speed Regulation
Control
Configuration
Temperature
Range
Specifications Bill of Material (Standard)
Standard: 230/460 60hz.,
Other voltages available
5 - 30HP for Compact Construction.
50 - 250HP with external SCR's
Typical 10 to 1
10% Typical
Static reversing.
- 40 degree C to
+ 55 degree C.
Type 4922C Variable Speed Control Assembly
Type 5410 Thyristor Power Module
Directional Relays
Syncronous Transformer
Current Transformer
Main Knife
Main Line Contactor
Overload Relay
Control Circuit Knife Switch
Control Circuit Transformer
Control Circuit Fuses
Tachometer Continuity Assembly
Description Symbol Qty.
Hubbell Industrial Controls, Inc.
A subsidiary of Hubbell Incorporated
4301 Cheyenne Dr., Archdale, NC. 27262
Telephone (336) 434-2800 • FAX (336) 434-2803
http://www.hubbell-icd.com
Sales@hubbell-icd.com
VSC
TPM
CR
ST
CT
MKS
M
OL
CKS
CTR
CFU
TCA
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5
2
1
1
1
1
3
1
1
2
1