Schweitzer Engineering Laboratories SEL-701-1, Instruction Manual

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SEL-701-1 Monitor
Date Code 20011009
Introduction and Specifications
SEL-701-1 Monitor Protection Features
1.6
SEL-701-1 Monitor Protection Features
The SEL-701-1 Monitor offers a full range of elements for motor protection,
including:
Flexible motor thermal element (49) that provides integrated
protection for locked rotor, running overload, unbalanced
current/negative-sequence current heating, and repeated or frequent
starts.
Phase, neutral, residual, and negative-sequence overcurrent (50)
elements for tripping due to motor or cable short circuits.
Load-loss and load-jam protection.
Antijogging protection (66) function using minimum time between
starts and number of starts per hour limit functions.
Unbalance current (46) element and phase reversal (47) element
protection.
Optional RTD inputs through an 11-input internal RTD option or
through purchase of the SEL-2600 RTD Module. The SEL-2600 RTD
Module connects to the monitor through a fiber-optic cable and
provides 12 RTD inputs plus an additional contact input. Select the
RTD type for each input from a list of four popular types. Each RTD
input has 1 TRIP and 3 ALARM setpoints
Optional voltage inputs that support four-wire wye, open-delta, or
single-phase voltage inputs and provide voltage-based protection and
metering functions. Added functions include over- and undervoltage
elements, over- and underfrequency elements, underpower elements,
reactive power elements, power factor elements, plus power and
energy metering.
Support to control contactors or medium-voltage motor circuit
breakers.
Fail-safe and nonfail-safe settings for monitor output contacts.