Specification Guide

Specification Guide

1.0General

1.01The electronic overload relay shall be available in NEMA and IEC contactor mount configurations.

1.02The electronic overload relay shall be capable of being applied to single- and three-phase AC squirrel cage induction motors. For single-phase applications, only two phase connections to the electronic overload relay shall be required.

1.03The electronic overload relay shall have current ratings ranging from 0.4 to 5000 amperes.

1.04TheFLA (full load ampere) setting adjustment range shall be a minimum of 5:1 (e.g. 9 - 45A).

1.05True RMS current measurement shall be accomplished with the use of hall-effect current sensors through 90 amperes; above 90 amperes, external torroid type current transformers may be used as input to the electronic overload relay.

1.06The electronic overload relay shall be capable of measuring current over a frequency range of 20 to 250 Hz.

1.07Supply voltage to the electronic overload relay shall be sourced from the 24V DC DeviceNet network supply.

1.08The internal power supply of the electronic overload relay shall provide reverse polarity protection,as well as limit the inrush current to less than 3A, to allow for multiple units to power up on DeviceNet simultaneously.

1.09A dedicated Trip relay with Form A contacts shall be provided for use in the motor starter control circuit. Trip relay operation shall be “fail-safe” such that the contacts are in the open state with supply voltage power removed.

1.10The electronic overload relay shall incorporate auxiliary relay outputs with Form A contacts that can be mapped for network use. Options shall exist for one or two outputs.

1.11All relay contacts shall be rated B300.

1.12The electronic overload relay shall incorporate 24V DC ratedinputs that can be mapped for network use. Options shall exist for two or four inputs. 120V AC inputs shall be accommodated by an interface accessory.

1.13A Test/Reset button shall be provided on the front of the electronic overload relay for the dual purpose of testing relay trip operation or resetting a trip.

1.14LED indicators shall provide status indication of network communications, trip and warning conditions, and input and output states.

1.15Trip and warning cause shall be identified usinga flashing code on the Trip/Warn LED indicator.

1.16Terminal identifications shall comply with CENELEC standards.

2.0Construction

2.01The electronic overload relay shall direct mount to the motor starting contactor.

2.02Type I and II short circuit coordination shall be provided in combination the associated motor starting contactor.

2.03The electronic overload relay shall incorporate a one piece insert-molded power terminal assembly.

2.04IEC configurations shall incorporate a latching mechanism for robust connection to the contactor base.

2.05IEC configurations shall be capable of being separately mounted with the use of a panel mount adapter accessory.

2.06The width of the electronic overload relay shall not exceed the width of the contactor.

2.07The electronic overload relay shall incorporate load terminals (T1/2, T2/4, T3/6) for direct connection of the motor cables.

2.08Wiring terminals shall provide IP20 finger protection.

2.09Versions offering ground fault protection shall incorporate the core balance (zero sequence) sensor into the electronic overload relay. Higher current devices that utilize external current transformers for phase current measurements shall provide connections for an external sensor.

2.10The electronic overload relay and accessories shall be rated for an operating environment of -20 to +55C (-4 to +131F).

2.11The electronic overload relay shall be capable of operating in an environment with a relative humidity range of 0 to 95%, non-condensing.

2.12The electronic overload relay shall be able to withstand a shock of 30G (per IEC 68-2-27).

2.13The electronic overload relay shall be able to operate without disruption for vibration levels up to 3G (per IEC 68-2-6).

2.14The electronic overload relay shall be able to operate without de-rating to an elevation of 2000m.

3.0Protection Functions

The electronic overload relay shall incorporate the following protection function capabilities. Settings shall be software programmable or by means of a handheld terminal. Settings shall be stored to nonvolatile memory.

3.01Thermal overload

Trip class setting range of 5 to 30

Reset mode adjustable for manual or automatic reset

Reset level setting range of 0 to 100% TCU

Warning level setting range of 0 to 100% TCU

Nonvolatile thermal memory circuit

3.02Phase Loss

Inhibit on start setting range of 0 to 250 seconds

Trip threshold factory set for 100% current imbalance