Eaton EMR-3MP0 - Anti-Backspin Delay Time (ABS); External Start Blocking; Thermal Block

If the motor reaches the »NOCS« limit in a cold start sequence, the »NOCSBlocked« block
signal is set and the »TBS« timer is started. When the »TBS« timer elapses while
the »NOCSBlocked« block signal is still set, the cold start sequence is terminated and
the »NOCSBlocked« block is released. Meanwhile, the »SPH« will start to count at the last
start in the complete cold start sequence.
4.2.7
Stop Cycle
The run cycle continues until the motor current level falls below the Stop Current
Threshold setting current on all three phases. Then a stop is declared. The start limits
(also referred as Jogging start limits) and the anti-backspin time delay (ABS) are checked.
If blocking conditions exist, the protective device can be con󰊎gured to block a motor from
starting. Remaining jogging block times are displayed and counted down, indicating how
long to wait. If there are no such starting block conditions in e󰊍ect, the protective device
is ready for a new start.
4.2.8 Anti-Backspin Delay Time (ABS)
»ABS« sets the time in seconds before a motor restart is permitted after a trip or stop
condition. This function can be set to »inactive«.
This function is used with a motor driving a pump working into a head, or any other load
that tends to spin in a reverse direction (backspin) when the motor is de-energized. It
blocks starting during the time when the motor might be rotating in reverse following a
trip. Also, this function may be used simply to set idle time (time between stop and start)
before a restart is permitted.
4.2.9
External Start Blocking
A motor can be blocked through a digital input. If this feature is enabled, the User must
make sure that both the Motor Start and Digital Input modules are con󰊎gured properly.
4.2.10
Thermal Block
Besides the previously mentioned start monitoring and controlling means, the motor can
be blocked if the thermal capacity used exceeds the alarm level. It is the user’s choice to
turn on or o󰊍 this feature and set an appropriate alarm level in the thermal model module
(see ╚═▷ “49 – Thermal Model”).
4.2.11 Blocked Condition
Note that the protective device has two types of blocking outputs: individual block and a
general block. The individual blocking functions are as follows:
•
Number of cold starts block;
• Time between starts block;
148 www.eaton.com EMR-3MP0
4 Protective Elements
4.2 Motor Starting and Control Module