Eaton Freedom NEMA Contactor Starter Complete Guide

Code current regulation range (A) applicable to NEMA size

A 0.33–1.65 00,0,1

B 1–5 00,0,1

C 4–20 00,0,1

D 9–45 0,1,2

E 20–100 2,3,4

F 28–140 4

G 60–300 5

H 120–600 6

Chapter 4 Key Selection Points and Engineering Techniques

4.1 Select NEMA size based on motor power

NEMA size does not correspond linearly to current, but is based on typical motor power. The following is the maximum HP reference at 460V/60Hz:

NEMA size continuous current (A) maximum HP (460V)

00 9 2

0 18 5

1 27 10

2 45 25

3 90 50

4 135 100

5 270 200

6 540 400

7 810 600

8 1215 900

9 2250 1600 (for consultation)

When selecting, it is necessary to check the full load current (FLA) and locked rotor current (LRA) on the motor nameplate, and ensure that the current rating of the contactor and overload relay is not lower than FLA. For high inertia loads or frequent starts and stops, a larger size should be selected.

4.2 Overload Relay Selection: Bimetallic vs Solid State

Bimetallic OL overload

Using interchangeable heater packs, each size corresponds to a set of heater selection tables (see sample Tab 15).

Advantages: Low cost, resistance to electrical noise, no need for external power supply.

Disadvantages: The environmental temperature has a significant impact (although there is environmental compensation), the setting range is narrow (usually 3:1), and the disengagement level is fixed (usually Class 20).

Attention should be paid when selecting: Non combination starters do not include heater packs and must be ordered separately (3 per box, corresponding to three phases). For dual speed starters, two sets of heater packs (one set per speed) need to be ordered.

C440 Solid State Overload (Solid State OL)

Wide tuning range (5:1), for example, code C for 4-20A can cover 4-20A, significantly reducing inventory.

Adjustable release level (Class 10/20/30) to adapt to different load characteristics.

Built in phase loss, phase imbalance, and ground fault protection (R64 should be selected).

Support remote communication (optional I/O module), capable of real-time reading of three-phase current RMS values, thermal memory, and fault records.

Self powered (no external power supply required), but requires an auxiliary power supply for communication.

Attention: Solid state overload is optional in starters of size 00~2 (modify code), and size 3 and above are also optional.

4.3 Short circuit protection devices in combination starters

Fusible type

Use Dual Element Time Delay Fuses, typically Class R, J, or H.

Rated short-circuit current: 100000 rms symmetrical current (480V and below), compatible with fuses to achieve Type 2 coordination - i.e. contactors and overload relays can still be used after a short-circuit fault.

When selecting, the current level of the fuse clip should be specified (30A, 60A, 100A, 200A, 400A, 600A, etc.), and the fuse itself should be provided by the user separately.

Circuit Breaker

Usually Eaton's HMCP (molded case circuit breaker) or MCP (motor protection circuit breaker) is used.

Short circuit rating: 100000 rms @ 480V, 25000 rms @ 600V.

The setting current of the circuit breaker needs to be adjusted according to the motor FLA setting.

For sizes 5 and above, the FLA and design code (such as Design B/E) of the motor need to be provided in order to correctly select the circuit breaker.

Non Fusible

Only provide isolation switch, no overcurrent protection. Short circuit protection must be provided upstream (such as fuses or circuit breakers on the distribution panel).

4.4 Selection of Control Transformer (CPT)

For situations where the voltage of the control circuit needs to be different from that of the main circuit (such as 480V for the main circuit and 120V for the control circuit), models with CPT (such as ECN07, ECN18, ECN24) can be selected. The CPT code example is as follows:

Code primary voltage (wiring method) secondary voltage

B 240/480 connected to 240V 120V

C 240/480 connected to 480V 120V

D 600V 120V

E 208V 120V

Q 208V 24V

Connect R 240/480 to 240V 24V

S 240/480 connected to 480V 24V

CPT capacity typically ranges from 50VA (small size) to 400VA (large size), sufficient to drive contactor coils and a few indicator lights.

Chapter 5 Installation and Wiring Practice

5.1 Precautions for Mechanical Installation

All Freedom contactors and starters can be installed horizontally or vertically on upright panels.

Adopting straight through wiring: the incoming terminal is at the top and the outgoing terminal is at the bottom. The screw type power terminal is equipped with a self lifting pressure plate, which can accommodate AWG 22~18 (0.3~0.75mm ²) wires.

Terminal screw torque: 0.5~0.6 N · m (control terminal), power terminal according to product label.

For combination starters, please note that the fuse clip of the fuse type model is only suitable for Class R fuses. If Class H or J is required, the modified code must be specified.

When safety door interlocking is required, the Type 12 enclosure needs to add modification code E11 (otherwise, standard Type 12 does not have door interlocking).

5.2 Coil replacement and wiring

The 45mm contactor magnetic circuit coil adopts dual voltage/dual frequency packaging (such as 120/60-110/50), and the coil terminals are located at the top for easy wiring.