SEL-701 Motor Protection Relayadmin2015-10-06T08:58:59+00:00
Project Description
SEL-701 Motor Protection Relay
The SEL-701 Motor Protection Relay provides locked rotor, running overload, and negative sequence current unbalance protection using a patented thermal model. The thermal element accurately tracks the heating effects of load current and current unbalance while the motor is accelerating and running. You can choose from three easy settings methods:
Motor nameplate ratings
45 standard thermal limit curves
Custom curve fitting
Functional Overview
14
Speed Switch
27
Undervoltage
37
Underpower
46
Current Unbalance
47
Phase Reversal
49
Motor Thermal
50N
Neutral Overcurrent
50
(P,G,Q) Overcurrent (Phase, Ground, Neg. Seq.)
55
Power Factor
59
Overvoltage
60
Loss-of-Potential
66
Starts-Per-Hour
81
(O,U) Over-/Underfrequency
DFR
Event Reports—Motor Starts, Motor Operating Statistics
LDP
Load Data Profiling
SER
Sequential Events Recorder
VAR
Reactive Power
* Optional
Front- and Rear-Panel Diagrams
Front
Rear
Motor Thermal Protection
The SEL-701 Motor Protection Relay provides locked rotor, running overload, and negative-sequence current unbalance protection using a patented thermal model. Add the voltage input option for metering and voltage-based protection elements.
Nameplate, Standard, or Custom Curve Setting Methods
Set protection using motor nameplate data, choose from 45 standard curves, or create custom protection curves for advanced protection.
Advanced Reporting
Motor start reports and motor start trend data support maintenance by indicating load problems early. The load profiling function tracks motor loading and use, storing quantities every 15 minutes for up to 48 days.
Internal or External RTD Module
The SEL-701 is available with an optional internal resistance temperature detector (RTD) module that monitors up to 11 RTDs. The relay offers thermal trips and alarms, thermal model biasing, RTD open or short alarms, and temperature measurement when equipped with RTD inputs.