Hamilton Sundstrand Company ACT2000 - Manual (Page 45)

3.6 Resetting the Actuator
To reset the ACT2000, +24 VDC must be applied across the RESET
wires for at least 0.5 seconds. The leading edge of the RESET command
causes the ACT2000 to stop all other operations, but the actual resetting
of the ACT2000 does not begin until RESET is returned to its OFF state.
The RESET command causes the ACT2000 to reset all internal position
indicators, reload all Set-Up parameters, and check the health of the
electronics. See the flow chart in Figure 3-1 for an illustration of this. The
ACT2000 is now in the Power Up / Reset state.
Once the RUN command is detected as ON, the actuator will then move
through its initial homing sequence again. RUN and DEMAND inputs are
ignored during the RESET command.
If FAULT alarm is detected, toggling the RESET command will clear the
FAULT alarm, but it will NOT clear the fault file.
3.7 Monitoring System Health
The firmware program continuously monitors system health while the
ACT2000 is powered. If any of the health parameters are out of the
normal operating range, the MCE outputs a discrete fault alarm to the
user’s controller.
Some fault causes are:
• MCE over-current
• Tracking error
• RDC failure
• Input voltage out of range
Fault Alarms
The ACT2000 features two discrete, non-latching outputs that are
configured as fault alarms. Upon power-up, the fault circuits close and
stay closed in the normal operating condition. When the ACT2000 detects
a system fault, it opens the fault circuit designated for that particular fault.
If a fault alarm is detected, the user should shut down the ACT2000 to
investigate the failure cause. Removing 120 VDC power shuts down the
ACT2000 actuator.
Toggling the RESET command will clear the alarms.
CH. 3: OPERATING THE ACT2000 39