Rockwell Automation Allen-Bradley E300, User Manual

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190 Rockwell Automation Publication 193-UM015D-EN-P - February 2015
Chapter 6 Protective Trip and Warning Functions
Over Voltage Protection
The winding insulation for electric motors degrades faster when more voltage is
supplied to the motor than the motor nameplate rating. This can damage to an
electric motor over an extended period of time. The E300 Electronic Overload
Relay can monitor for this condition with its Over Voltage Trip and Warning
function to detect for high voltage levels to minimize motor damage and loss of
production.
Over Voltage Inhibit Time
Over Voltage Inhibit Time (Parameter 359) allows you to inhibit an over voltage
trip and warning from occurring during the motor starting sequence. It is
adjustable from 0…250 seconds.
Over Voltage Trip
The E300 Electronic Overload Relay trips with an Over Voltage indication if:
• No trip currently exists
• Over Voltage Trip is enabled
• Voltage is present
• Over Voltage Inhibit Time has expired
• The minimum phase voltage is greater than the Over Voltage Trip Level
for a time period greater than the Over Voltage Trip Delay.
If the E300 Electronic Overload Relay trips on an over voltage, the:
• TRIP/WARN LED status indicator flashes a red 1-long / 2-short blink
pattern
• Bit 1 in Voltage Trip Status (Parameter 5) sets to 1
• Bit 0 in Device Status 0 (Parameter 20) sets to 1
• Any relay outputs configured as a Trip Relay open
• Any relay outputs configured as a Control Relay open
IMPORTANT
The Under Voltage Warning function does not include a time delay feature.
Once the Under Voltage Inhibit Time has expired, the Under Voltage Warning
indication is instantaneous.
Default Value 10.0
Minimum Value 0.0
Maximum Value 250.0
Parameter Type USINT
Size (Bytes) 1
Scaling Factor 11
Units Seconds