41
Logix
®
520MD+ and 510+ Digital Positioners FCD LGENIM0105-15-AQ – 05/16
flowserve.com
Upgrade Level Icons - The upgrade levels provide increased func-
tionality beginning at none, then Standard, Advanced and finally Pro.
These levels also correspond to the model numbers 510+, 520MD+,
521MD+ and 522MD+ respectively. A 510+ positioner has limited
diagnostics and cannot be upgraded. A Standard (520MD+) has posi-
tioner position-based diagnostics and can be upgraded to a 521MD+
in the field. An Advanced (521MD+) positioner includes pressure sen-
sor functions and can be upgraded to a 522MD+ in the field. A Pro
(522MD+) positioner includes the pressure sensor functions along
with full diagnostic capabilities and is fully upgraded.
Command Source Icons – The positioner is in Analog Command
mode if it is using the 4-20 mA signal to control the location of the
valve. In Digital Command mode, the positioner ignores the 4-20
command and responds to the position command given through
HART. In Out Of Service mode, the positioner is performing a calibra-
tion, signature, partial stroke test or is in a factory reset state.
Training Mode Icons – The positioner can keep track of several key
data parameters for a period of time specified by the user. This data
can be viewed while setting alarm limits to make them more mean-
ingful. For example, if supply pressure cycles every day from 5 bar
to 4 bar in normal operation, this information will be displayed where
the supply pressure warning limits are set. Seeing that the supply
typically drops to 4 bar, the user can then set the supply pressure low
warning to a value below 4 bar. See the DTM User Manual for more
information.
Pressure Control – When the position of the valve gets very close
to the commanded position, the positioning algorithm will change
to pressure control. This means the pressures will be held constant
(locked), improving the stability of the valve position. The point at
which the pressure control is locked depends on the Valve Stability
switch on the positioner. When the switch is set to “Lo Friction”, the
locking point is self-adjusting to optimize accuracy. When the switch
is set to “Hi Friction” and the deviation is smaller than +/- 1.0%, the
pressure “locks”. This value can be adjusted using the Display Menu
or DTM. See section 10.3.7 Configuration (Pressure Control).
HART Communications Icons – When the positioner is sending or
receiving data via the HART communication protocol, the icon will be
displayed. During burst mode, a pulsating heart icon will be displayed.
Continuous Stroke Test (CST) – For valves that are normally held at a
constant position for extended periods of time, the Continuous Stroke
Test can provide assurance that the valve is still responsive. When
CST is on, the positioner will cause a very small amount of valve
movement. From this movement, the positioner can find information
about the health of the valve, actuator and positioner. This is not
recommended for valves intended for high accuracy or stability.
To achieve the CST function, the positioner adds a small deviation to
the command. The deviation is ramped at a rate of 0.05%/second up
to 5%. However, the instant the valve moves, the ramp reverses and
begins to grow in the opposite direction. So, with low friction, the
actual movement will be quite small. If the valve does not move by the
time the deviation equals 5%, a counter will start. After 5 consecutive
failed attempts to move, the CST warning will appear. The ramp rate,
maximum limit, and frequency of the CST can be adjusted using the
DTM.
10.1.5 Adjusting the Display Contrast
To adjust the display contrast, hold the
,
Back button for 3 seconds.
Use the
.
Up and
.
Down buttons to adjust the contrast. Use the
.
ACCEPT/QUICK-CAL to accept the settings.
Figure 38: Display Main View
