EATON FP-4000 feeder protection relay

EATON FP-4000 feeder protection relay

Product Overview

Cutler Hammer under Eaton ®  FP-4000 feeder protection relay is a multifunctional protection device based on microprocessors, designed to provide comprehensive monitoring, protection, and control for medium voltage main incoming circuit breakers, bus tie circuit breakers, and feeder circuit breakers. It integrates three-phase overcurrent, ground fault, voltage protection, and energy measurement functions into a compact fixed chassis that meets ANSI and UL standards, significantly reducing panel space, wiring, and costs.

FP-4000 fully utilizes microprocessor technology to provide users with rich data acquisition functions and unprecedented flexibility. It continuously self checks all hardware and firmware protection components to ensure reliable operation in the event of system or component electrical failure. Its protection function is widely applicable to main incoming lines and distribution feeder circuits, and its programmable logic control function makes it particularly suitable for main tie main and dual main incoming line switching schemes.

Application Description

FP-4000 is mainly used in medium voltage switchgear as the primary protection for feeders, incoming lines, and bus tie circuit breakers. It can also serve as a backup protection for transformers, high voltage lines, and differential protection. Its typical applications include:

Main incoming line protection: provides complete overcurrent, ground fault, and voltage protection.

Feedline protection: provides sensitive selective protection for distribution lines.

Bus tie circuit breaker control: supports main bus tie main automatic switching logic to enhance power supply reliability.

Backup protection: Provide reliable backup when upstream or downstream protection fails.

Through the Zone Interlocking function, FP-4000 can directly cooperate with Cutler Hammer Digitrip 3000 and Digitrip MV relays to achieve busbar protection, replacing the expensive and complex busbar differential (87B) scheme. The newly added breaker failure logic can quickly trigger remote backup clearing when the circuit breaker refuses to move, significantly reducing the fault removal time.

Core protection function

FP-4000 provides comprehensive and flexibly configurable protection functions, covering multiple dimensions such as current, voltage, frequency, etc. The following is a list of its main protection functions (see Figure 1 for a single line diagram):

1. Phase overcurrent protection

Two stage instantaneous overcurrent (50P-1, 50P-2): with independent timer, can set instantaneous or short delay.

Inverse time overcurrent (51P-1): Supports 10 standard characteristic curves (such as Mod, Very, Extremely, IECA, IECB, IECC, I ² t, etc.), and can choose instantaneous reset or delayed reset.

Setting range: starting value of 0.1~4.0 pu (step size 0.01), time multiplier of 0.05~10.0 (step size 0.01), instantaneous starting value of 0.1~20.0 pu (step size 0.01).

2. Grounding overcurrent protection

Similarly, it provides both inverse time limit and instantaneous two-level protection, with a setting range similar to phase overcurrent.

3. Voltage imbalance protection (47)

Monitor the ratio of negative sequence voltage to positive sequence voltage (% V2/V1), set a startup threshold of 4% to 40% (step size 1%), and set the minimum voltage threshold (1~100V) with a delay of 0~9999 cycles.

4. Current imbalance protection

Monitor the ratio of negative sequence current to positive sequence current (% I2/I1), with a startup threshold of 4% to 40% (step size 1%), a minimum current threshold of 0.1 to 20.0 pu, and a delay that can be set.

5. Undervoltage/Overvoltage Protection

The voltage setting range is 10~150V (step size 1V), with a delay of 0~9999 cycles.

6. Underfrequency/Overfrequency Protection

The frequency setting range is 45~65 Hz (step size 0.01 Hz), with a delay of 0~9999 cycles.

7. Circuit breaker failure protection

The current starting value is 0.1~5.0 pu (step size 0.01), with a delay of 0~9999 cycles.

8. Power factor protection

Trigger/reset threshold 0.5 lag~0.5 lead (step size 0.01), delay 0~1000 seconds.

Measurement and measurement accuracy

FP-4000 is not only a protective device, but also a high-precision energy meter that provides complete measurement of power parameters:

Phase current accuracy: ± 0.5% or ± 0.025A (0.02-20 pu full offset waveform)

Grounding current accuracy: ± 0.5% full range (0.02~2.0 pu)

Phase voltage accuracy: ± 0.5% or ± 0.2V (0~160 Vac)

Frequency accuracy: ± 0.02 Hz

Phase angle accuracy: ± 1 °

Power accuracy: ± 1.5%

Clock accuracy: Free running ± 1 minute/month (25 ° C), automatically calibrated by PowerNet host

In addition, FP-4000 can record demand, minimum/maximum values, and provide up to 40 days of load trend data to help users optimize energy use.

Event recording and fault analysis

When there is a disturbance or fault in the power system, FP-4000 immediately stores the following data in non-volatile memory:

Voltage and current sampling data

Calculated values (such as power, demand)

Internal protection component status

Logic Input Output Status

Fault recording capability: