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SA FEG E A R® MOTOR CONTROL CE NTE R/A RC- R E S I STA NT M ETA L- CL A D CON STRUC TI ON
All contactors must be in “DISCONN.” position, when service or maintenance personnel are working on the
MCC, unplug the main bus feed and ground the whole system.
Before energizing the MCC, do a complete review of the mechanical operation of all devices. Remove clips of
the relays, contactors, meters, etc.
Manually operate all contactors and relays. Moving parts should not bend. Verify that there are no foreign
objects in the equipment.
Use compressed, clean, dry air to clean all inside and outside surfaces.
Note: Current transformers secondary circuits should be short circuited.
Clean contact surfaces with a clean cloth and an OSHA approved solvent. Bolt the bus together. Conductivity
of a bolted joint depends with the proper torquing of the bolts.
All contact surfaces of the bus will be bolted and plated.
Clean all surfaces with a clean cloth and use only OSHA approved solvent. Join bus bars with the correct
screws a good conductivity depends of the appropriate torque applied.
Energizing main bus
After completing the control circuit checkout, energize the main bus as follows:
1. Verify that all doors and panels are in place and secured. All contactors must be racked out (“DISCONN.”).
2. Energize the incoming bus to the equipment’s main circuit breakers or any other device located in the incoming
of the lineup.
3. Verify if operation of instruments and relays are correct.
4. Activate the independent control power source.
5. Energize the main bus closing the main circuit breaker; verify that the relays and other instruments are functioning
correctly.
6. Place the contactors from the out position (“DISCONN.”) to the inserted position (“CONN.”).
7. Close the desired contactors.
Standard construction
Contactor compartment
The principle of manufacturing is modular, for 400 and 720 A contactors the compartment dimensions are
30” wide, 33.625” deep and 38” high. For control low voltage (LV) compartment the dimensions are 30” wide,
15.12” deep, and 19” or 57” high. For main bus and cable compartment rated at 1200, 2000 and 3000 A the
dimensions are 30” wide, 31.38” deep and 95” high. The general dimensions of the SafeGear™ MCC are 30”
wide, 68” deep and 95” high without plenum (21 in extra).
The compartments are manufactured of galvanized steel material. The main parts of each compartment are
designed with a double-bend in the end sides in order to get higher mechanical strength. The contactor truck
has a galvanized steel base with wheels, in which are set the contactor and the fuses box. Three phases are
connected by finger contacts.
The new design of the contactor truck allows manual insertion only when the contactor compartment door
is closed, using a tool (racking lever). The secondary automatic system is auto adjustable so it does not
require manual connection.
The standard paint color is Grey ANSI 61. This powder paint has an electrostatic finish applied in a ferrous
phosphate covering. This process reaches uniform and soft texture. Pieces that are not painted are fabricated
with C.R.S. (Cold Rolled Steel) galvanized.
Painted pieces are of black sheet C.R.S. or could have another finish to meet the IEEE C37.20.2.
