RD1-
“RD1” is the rapid cycle timer. To view and adjust RD1, TC must not be
J00. It will engage when the motor is first powered-up or after the motor
controls shut down the motor. An “RD1” setting of 20-30
second
s will
generally protect the motor from rapid, successive power outages or short
cycling caused by the motor controls. A setting of
0 (zero)
will allow the
motor to start immediately after power-up or after a normal shutdown.
Note:
In linear trip mode (TC = J00), the RD1 time is appoximately 50% of
the normal RD1 time. Example: If RD1 is set to 10
seconds
, the
TC = J00, then the actual RD1 time in the linear trip mode will be 5
seconds
.
Note: Display increments by 2.
RD2-
“RD2” is the restart delay after the overload relay trips on current unbalance,
single phasing, and overload (if “oc” is programmed in “#RF”). To view and
adjust RD2, TC must not be J00. This delay allows the motor to cool down
after experiencing the above faults. It is also known as a motor cool down
timer. Your motor manufacturer should be contacted to determine this
setting. Under normal circumstances, a setting of 30-60 minutes will give
the motor enough time to cool down between faults. The Motor
Manufacturer should be consulted for their recommendation.
MA-
In linear trip mode (TC = J00), the RD1 position becomes the motor
acceleration time. To view and adjust MA, TC must be J00. The motor
acceleration time is related to the load on a motor. For high inertia loads
such as fly wheels or conveyor systems, the motor acceleration time is
considerably longer than low inertia loads such as submersible pumps.
Therefore, “MA” is typically set higher for high inertia loads and lower for
low inertia loads. During the motor acceleration time, the linear overcurent
trip feature is ignored. Therefore, it is important not to set “MA” too high
because damage could occur to the motor. The minimum MA time is
0.158 seconds. The actual MA time is the display value times 0.158
seconds (
±
0.315 seconds). Example: If MA is set to 60, MA Time = (60 x
0.158 seconds) = 9.48 seconds
±
0.315 seconds.
Note: In linear trip mode (TC = J00), the RD2 time is appoximately 50% of
the normal RD2 time. Example: If RD2 is set to 10 minutes, the
TC = J00, then the actual RD2 time in the linear trip mode will be 5
minutes.
OCTD-
In linear trip mode (TC = J00), the RD2 position becomes the
Overcurrent Trip Delay. To view and adjust OCTD, TC must be
J00. This setting represents the maximum time that the
unit will tolerate an overcurrent condition before tripping.
The minimum OCTD time is 0.158 seconds. The actual OCTD is the
display value times 0.158 seconds (±0.315 seconds). Example: If
OCTD is set to 6, OCTD = (6 x 0.158 seconds) = 0.948 seconds ±0.315
seconds.
-7-
07/25/03
