ABB 300 Series - User Manual

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Figure 1 — reference diagram (representation only)
A
Coil
B
Overload relay
Heater slots
Magnet
assembly
Adjustment
dial
C
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Figure 2 — reference diagram (representation only)
Magnet
assembly
Overload relay
Circuit breaker
or molded
case switch
Pilot devices
Accessories
Lifting brackets
(not shown)
1
CAUTION
Before installing in a nuclear application,
determine that the product is intended
for such use.
WARNING
Disconnect power before installing
or servicing.
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Ratings
Max.
voltage
Max.
continuous
amp rating AC volts
Max. HP for
AC motors
Poly-phase
   
 
 
Description

motor starter consists of a magnetic

relay and a manually operated circuit
breaker or disconnect switch. The
disconnect switch may either be fusible

switch provides a means of manually
disconnecting the motor from the line.
The circuit breaker or fusible disconnect

circuit protection. The overload relay
provides motor protection against
running and stalled motor overload.
The overload relay is provided with a
yellow trip indicator, located to the right
of the reset arm and visible when the
overload relay is tripped.
Features
1. Strongbox coil.
2. Overload relay, incorporates a dial
for ±10% field adjustment of tripping
current, so that it is no longer
necessary to change heaters to
eliminate such problems as nuisance
tripping in hot weather.
3. Overload trip indicator.
 
5. Oversized power terminals will
accommodate up to 2 runs of
500 MCM wire.
6. Starter can be disassembled and
inspected in a matter of seconds.
7. Circuit breaker or disconnect switch
is mechanically interlocked with the
enclosure door to prevent opening
the door until the handle is moved
to the OFF position.
Installation
Before connecting the starter:
1. Remove all packing.
2. Clean magnet mating surfaces
of any dust or foreign matter.
3. Select heaters in accordance with
heater table, which accompanies
each device.
 
operating arm by pressing on the
nameplate to assure free movement.
5. Mount the starter on a sturdy
vertical support.
6. The overload relay may be reset
manually by depressing and releasing
the reset arm. Overload relays with an
optional normally open contact are
electrically isolated from the normally
closed contact.
7. Provide motor branch circuit protection
in accordance with the National
Electrical Code.
Coil removal
The encapsulated coil is impervious to
moisture, dirt and oil. It resists mechanical
damage and failure due to high humidity.
No tools are required to remove coil.
1. Remove power from device.
2. Unscrew one end of the retainer (B —
figure 1) and slide it out of the slot.
3. Remove movable magnet assembly.
 
figure 1) . Press against coil and pull up
and out on coil retainers (A — figure 1).
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INSTALLATION INSTRUCTIONS FOR NEMA SIZE 6
300/400-line magnetic motor starters

Summary

300;400-line Magnetic Motor Starters

Safety and Warnings

Critical safety notices including CAUTION and WARNING for installation and servicing.

Installation

Step-by-step instructions for connecting the starter, including preparation and mounting.

Coil Removal

Steps for safely removing the encapsulated coil from the magnetic starter assembly.

Maintenance and Troubleshooting

Contact Removal

Procedure for inspecting and replacing movable and stationary contacts without tools.

Overload Relay Contact Check

Method to check for welded relay contacts using an operator or continuity test.

General Maintenance Tips

Recommendations for simple maintenance, cleaning magnet surfaces, and avoiding oil.

Principal Renewal Parts

Overview

1. Function Description
2. Usage Features
3. Maintenance Features

This document provides installation instructions for ABB 300/400-line magnetic motor starters, NEMA Size 6. These starters are designed for full voltage operation and consist of a magnetic contactor with a three-leg block overload relay and a manually operated circuit breaker or disconnect switch.

Function Description

The magnetic motor starter's primary function is to control and protect AC motors. It integrates a magnetic contactor for switching the motor on and off, and an overload relay for motor protection. The disconnect switch, which can be either fusible or non-fusible, provides a means of manually disconnecting the motor from the line. If fusible, it also offers motor branch short-circuit protection. The overload relay specifically protects the motor against damage from running and stalled motor overload conditions.

The overload relay features a yellow trip indicator, which becomes visible when the relay trips, signaling an overload event. This visual cue helps in quickly identifying the cause of a motor shutdown.

Usage Features

The ABB 300/400-line magnetic motor starters are built with several features to enhance usability and reliability:

• Strongbox Coil: The coil is encapsulated, making it impervious to moisture, dirt, and oil. This design also provides resistance to mechanical damage and failure due to high humidity, contributing to the starter's durability in harsh environments.
• Adjustable Overload Relay: The overload relay incorporates a dial for ±10% field adjustment of the tripping current. This eliminates the need to change heaters to prevent nuisance tripping, especially in varying temperature conditions like hot weather, offering greater flexibility and precision in motor protection.
• Straight-Through Wiring: This design simplifies the wiring process, making installation and maintenance more straightforward.
• Oversized Power Terminals: The power terminals are designed to accommodate up to two runs of 500 MCM wire, providing ample capacity for various wiring configurations.
• Disassembly for Inspection: The starter can be easily disassembled for inspection in a matter of seconds, facilitating quick checks and troubleshooting.
• Mechanical Interlock: The circuit breaker or disconnect switch is mechanically interlocked with the enclosure door. This safety feature prevents the door from being opened until the handle is moved to the OFF position, ensuring operator safety during maintenance or inspection.
• Easy Coil Removal: The coil can be removed without the need for special tools. The process involves unscrewing a retainer, removing the movable magnet assembly, loosening four coil retainer screws, and then pressing and pulling the coil retainers.
• Tool-Free Contact Replacement: Movable contacts can be inspected and replaced quickly without the use of tools. This simplifies maintenance and reduces downtime.

Maintenance Features

The design of these starters emphasizes simple and preventive maintenance to ensure long-term, dependable service.

• Welded Contact Check: The overload relay includes a feature that allows maintenance personnel to check for welded relay contacts. By depressing a white operator located at the top of the overload relay contact housing, an audible "click" indicates normal operation when the relay is in the reset condition. A continuity check can also be performed by disconnecting control wiring and using a bell set or resistance measuring instrument. This manual contact operation check provides positive assurance that contacts have not welded due to short circuits in the control wiring.
• Minimal Corrective Maintenance: 300/400-line starters and contactors require virtually no corrective maintenance, focusing instead on preventive measures.
• Cleaning: It is crucial to keep magnet mating surfaces free of accumulated dirt or dust. However, it is explicitly stated DO NOT OIL OR GREASE these surfaces.
• Contact Replacement Guidelines: Contacts are designed for maximum life and should only be replaced when nearly all the silver tip is gone and the contact tip support is exposed. It is important NOT TO FILE or otherwise dress the contacts, as this will result in lost tip material and reduce the contactor or starter life.
• Overload Relay Reset: The overload relay can be manually reset by depressing and releasing the reset arm. Overload relays with an optional normally open contact are electrically isolated from the normally closed contact.
• Coil Replacement: Replacement coils are available for two- and three-pole devices, with specific catalog numbers based on voltage and frequency.
• Arc Chute Cover: When reassembling, it's important to note that the arc chute cover fits only one way and is marked "TOP" in the upper right-hand corner. Users are advised NOT to attempt to remove or replace arc traps in the arc chute cover.
• Magnet and Movable Arm Reassembly: While the magnet and movable arm can fit either way, reassembling them in the same orientation as they were taken apart will result in quieter operation.

These features collectively contribute to the ease of installation, operation, and maintenance, ensuring the longevity and reliability of the ABB 300/400-line magnetic motor starters.

ABB 300 Series Specifications