Rockwell Automation T8442 Trusted TMR Speed Monitor - Manual (Page 26)

Trusted
TM
Module T8442
Issue 8 Apr 10 PD-T8442 26
3.1.5. Over-Acceleration Limit
This field can be set for each input group.
The input value configures the over-acceleration threshold ceiling in RPM/second. This defines the
maximum over-acceleration threshold level that can be set through the application interface. The over-
acceleration output will trip when the acceleration is greater than, or equal to, the configured threshold.
The range of values that can be used for this field are 0 to 10000. The default value is zero.
If the limit is set to zero, the over-acceleration trip threshold for the group will be disabled (i.e. always
tripped).
The configured limit may only be increased if the group is at zero speed.
The configuration will appear in the speed monitor configuration template as:
OAL
3.1.6. Over-Speed Deadband
This field can be set for each input group.
The input value configures the over-speed trip deadband (hysteresis) in RPM.
The deadband value defines the speed at which a tripped over-speed output will revert to the non-
tripped condition. The over-speed output will revert to the non-tripped condition at a speed determined
by (OSL - OSDB). Where OSL is the Over-speed Limit and OSDB is the Over-speed Deadband.
OSDB is used in both normal and over speed test modes.
NOTE: The associated over-speed output relay will not automatically return to the non-tripped state
unless it is configured with the non-latching attribute. Refer to section 3.1.13.
The range of values that can be used for this field are 0 to 30000. The default value is zero.
The configured deadband value may only be decreased when the group is at zero speed.
Consider the following example:
A channel has been configured with an over-speed trip threshold of 2000 RPM and an over-speed
deadband value of 100 RPM.
The channel will trip when the speed reaches or exceeds 2000 RPM and will not revert to the non-
tripped state until the speed falls to 1900 RPM or less.
The configuration will appear in the speed monitor configuration template as:
OSDB
3.1.7. Over-Acceleration Deadband
This field can be set for each input group.
The input value configures the over-acceleration trip deadband in RPM/second.
The deadband value defines the acceleration value at which a tripped over-acceleration output will
revert to the non-tripped condition. The over-acceleration output will revert to the non-tripped condition
at an acceleration determined by (OAL - OADB). Where OAL is the Over-acceleration Limit and OADB
is the Over-acceleration Deadband.
NOTE: The associated over-acceleration output relay will not automatically return to the non-tripped
state unless it is configured with non-latching attribute. Refer to section 3.1.13.
The range of values that can be used for this field are 0 to 10000. The value must be less than or
equal to the Over Acceleration Limit.default value is zero.
The configured deadband value may only be decreased when the group is at zero speed.