Beck, R&J ELECTRIC ACTUATORS FOR INDUSTRIAL PROCESSCONTROL 11-1_9 Manual De Usuario

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DCM-2 HART INTERFACE
 
Maintenance - Alarm Messages
Message
Description
“The Torque/Thrust is greater than the 
output rating”
“Motor power has been removed due to 
excessive output torque”
“The temperature is outside of –40F to 
185F”
"Demand Signal is out of limit"
"Loop Current Detected while under 
HART/FF Control"
"Loop Current Detected while set for LOS 
PAT"
This is a Beck-specific message that can appear after the HART
®
-
defined (“Process applied to the non-primary variable is outside 
the operating limits of the field device”) message mentioned 
previously.  It serves to further define the condition, and indicates 
that the drive’s torque output is exceeding 105% of the calibrated 
torque range of the drive.
This Beck-specific message appears after the “Torque is excessive” 
message if the torque measurement has exceeded 150% of the 
calibrated range and thus gone into a protective mode of operation 
to prevent excessive torque in the event of an obstruction or 
other problem.  The drive ceases driving against the load until the 
condition is reset.  Although unlikely, it is possible to also get a “Drive 
in stall” message (see misc. messages) with this message.
This is a Beck-specific message that can appear after the HART
®
-
defined (“Process applied to the non-primary variable is outside 
the operating limits of the field device”) message mentioned 
previously.  It serves to further define the condition, and indicates 
that the drive’s internal temperature is outside the -40° to 195°F 
(-40º to 91ºC) range.
The Demand Signal has exceeded its measurable limits and has 
entered saturation.  The value reported for Demand does not 
reflect the actual value.
This is a Beck specific alarm message that alerts the user 
that analog current is present on the Demand terminals while 
operating the drive using the HART configurator Manual Operation 
menu.  It is used to avoid confusion when a board is left in one 
of the manual operation modes and is not properly restored to 
"FOLLOW" mode.
PAT mode (Proportional mode) is a special Demand mode where 
discrete logic inputs are used in place of the Analog Demand 
signal.  When operating in PAT mode, no Demand current should 
be present.  If current is detected, this alarm will be asserted.
Position Signal Messages
(The position signal is defined as the signal from the position sensor (CPS) to the DCM-2)
Message
Description
“Process applied to the primary variable 
is outside the operating limits of the field 
device”
This is a standard HART
®
-defined message that appears 
whenever the HART
®
 primary variable (Position signal) is outside 
the design or calibrated range.  The DCM-2 is designed to accept 
a maximum position signal range of 0.25 to 5.35 V dc, and can be 
calibrated anywhere within this range depending on the type of 
CPS and desired stroke of the drive.  Normally, new drives would 
be calibrated for a 1–5 V dc position signal.  Retrofit applications 
are typically calibrated for a 0.45–2.6 V dc range.
Demand Signal and Process Variable Messages (con't)