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A1 STATUS
Motor status
4–4
MOTOR STATUS
Range: Tripped, Stopped, Starting, Running, Overload
The motor status is tripped following any protection trip operation or lockout. After all
protection trips and lockout have cleared, the tripped motor status can be reset from the
front panel reset key, by closure of the reset or lockout reset contact input, or via
communications. The emergency restart function also resets tripped status.
When the motor status is stopped, detection of phase current above the FLA changes
the status to starting. Running status follows starting when the current then drops
below FLA. Running status continues as long as phase current greater than 5% of CT is
detected. To accommodate applications where current does not rise above the thermal
overload pickup setting on start, running status is also declared when the contact inputs
indicate the motor is online. When phase current falls below 5% of CT the status
changes to stopped. To accommodate applications where motor idle current is less
than 5% CT, a further requirement to change status to stopped is that the contact inputs
do not indicate the motor is online.
For single speed applications, an enabled 52a contact input closed or an enabled 52b
contact input open is taken as indication of motor online. If both are enabled, the relay
assumes the motor is online if the 52a contact is closed and the 52b contact is open.
For two speed applications, closure either of the High Speed Switch contact input or of
the Low Speed Switch contact input is indication of motor online. If either 52a or 52b
contact input is enabled, a further requirement is that these indicate the breaker is
closed.
Use of these contact inputs (52a Contact, 52b Contact, High Speed Switch, Low Speed
Switch) for motor online detection is optional, but is recommended to ensure proper
detection of motor running, especially in cases where the starting current is less than the
thermal overload pickup setting or motor idle current is less than 5% of CT.
MOTOR LOAD
Displays the average 3-phase motor current (I
BIASED MOTOR LOAD
Displays the equivalent motor heating current (I
Thermal Protection section.
MOTOR TCU
Displays the Thermal Capacity Used.
MOTOR SPEED
Indicates the motor running speed per the speed switch input. This value is seen only
when the setting "Enable 2-SPD Motor" is enabled.
O/L TIME TO TRIP
Displays the remainder of the thermal overload trip time when the current is above the
thermal overload pick-up setting.
THERMAL INHIBIT
Time in seconds left until the Thermal Start Inhibit expires. Has a value of zero if this
feature is set to OFF, or if the time has expired.
STARTS/HR INHIBIT
Time in seconds left until the Starts per Hour feature's inhibit expires. Has a value of zero
if this feature is set to OFF, or if the time has expired.
CHAPTER 4: ACTUAL VALUES
) per-unit on an FLA base.
avg
) per-unit on an FLA base. Refer to
eq
339 MOTOR PROTECTION SYSTEM – INSTRUCTION MANUAL
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