Radius RX-500 Series User manual

Pneumatic
positioner
RX- 500 Series
1. GENERAL
The pneumatic positioner RX-500 is used for rotary operation of
pneumatic rotary valve actuators by means of pneumatic control
systems with an output signal of 3-15psi or split ranges.
2. FEATURES
• There is no resonance in the range of 5(200Hz.
• Performing 1/2 Split Control without any other substitutes.
• Easy to adjust zero and span.
• Easy to convert from Reverse Action to Direct Action or vice versa.
• Fast and accurate response
• Low air consumption
• Easy to protect from hunting effect by using output orifice in
small size of actuator.
• Designed as Multi-port type of for air tubing
• Easy to install air tubing connection in any direction
• Designed as modular structure for maintenance and repair
INSTRUCTION
MANUAL

3. Specifications
MAIN PARTS LIST

The movement of Actuator stem exerted force to the
Feedback Spring through Feedback Shaft connections.
Then Actuator will stop at the point of force balance
exerted by the input current signal and the feedback
spring.
Increase the input signal to change in lift position of
valve.
Force exerted by Torque Motor reduces Nozzle Back
Pressure with increase in gap between Flapper and
Nozzle. Then Spool moves upward and the Seat opens
simultaneously. Air pressure of OUT1 pipe is discharged
to Actuator. As pressure in the actuator chamber goes
up, Actuator stem start to move.
4. OPERATING PRINCIPLES
2) Cam attaching procedure
(1) Use the DA face of cam to turn
the actuator main shaft clockwise
(viewed from the positioner front cover
side) at the time of input feedback
shaft. Use the RA face to turn it
1 Example of attaching to actuator
Radius provides a stamped stainless
steel bracket (above right) for mount-
ing to the bottom of the positioner.
However the RX-1000 is drilled and
tapped on the side for side mounting
of a custom fabricated bracket (above
left).
5-2 Connection with feedback shaft.
All Radius brand positioners come
with the standard NAMUR type
spaded shaft for direct interface to all
Radius actuators and most all other
brands of rack and pinion actuators
manufactured with the NAMUR type
slotted top shaft. Because all Radius
positioners are supplied with a
stainless steel mounting bracket,
attachment to these types of actua-
tors is very simple.
counterclockwise (reverse action).
Correctly attach the cam to the flange
part of feedback shaft.
(2) Attach the cam in the procedure
of loosening the hexagonal nut with
flange first, setting the using actuator
to the starting position and then
setting the cam reference line and the
bearing contact point of span adjust-
ing arm unit to the matching position.
(3) Do not apply the supply pressure
when attaching the cam as otherwise
it is very dangerous.
(4) When the positioner is shipped out
of our plant, the cam is tentatively
tighened to the shaft. Be sure to firmly
lock the cam the lock nut [tightening
torque 2.0~2.5Nm(20~25kgfcm)].
5. INSTALLATION

8. AIR PIPING CONDITIONS
• Fully purge the pipe to remove
foreign matter.
• Use a clean supply air fully removed
humidity ad dust.
• Use YT-200 filter regulator to keep
supply air pressure constantly.
• When using the double acting type
as the single acting type, blind either
OUT1 or OUT2 and also remove the
pressure gauge to close its connec-
tion
6. AIR PIPING DIAGRAM

7. ADJUSTMENT PROCEDURE
1) Zero Adjustment
• Set an signal to the Stroke starting
signal(0.2kgt/_) then turn the Zero
Adjuster clockwise or counter-clock-
wise.
• In case of Spring Actuator, check if it
is set to standard pressure in Zero
Point. If not, repeat Zero adjustment.
2) Span Adjustment
• Turn and adjust Span Adjustment
Screw so that Indicator reaches at
final Stroke Point by final input signal.
• Check Zero Point and repeat Zero
Span Adjustment. 1/2 Split Range can
be used by Zero and Span Adjust-
ment.
After setting, tighten up Lock Screw
of Span adjustment.
3) Auto/Manual Switch
• This is a Switch for changing Auto
and Manual.
• Shipped products is set for Auto. To
use Manual operation, turns A/M
Switch
counterclockwise.
• In manual operation, the pressure of
YT-200 air filter regulator connects to
Actuator. After using, return switch to
“A”.
• Not available for Single Acting-
OUT2 and Double Acting.
4) Seat Adjuster
• No need to adjust at the field
because Seat Adjuster is to be
adjusted before shipment for bal-
anced pressure point of output
pressure.
• Seat Adjuster is always used for
Double-acting. If need to change
balanced pressure point of output
9. MAINTENANCE AND CHECK
• If the supply air is fouled, the
positioner may not operate normally.
Periodically check the compressed air
cleaning system and make sure that
clean air is always supplied.
• When you disassemble the pilot
valve, coat grease to the O-ring of the
sliding section.
• When the fixed orifice is clogged
with carbon particles or others,
remove the pilot valve Auto/Manual
changeover screw(built-in fixed
aperture) and clean it by inserting a
Ø0.2 wire into the aperture. If it must
be replaced with new one, stop the
supply pressure and remove the
stopper screw of the pilot valve.
• Check the positioner once a year.
When you find excessively worn
diaphragm, O-ring and other packing
or any unit, it should be changed with
new one. Treatment at an early stage
is especially import if the positioner is
used in a place of severe environ-
ment like coastal area.
10. WARNING
• Do not apply large vibration or
impact to the positioner. It causes
trouble. The positioner must be
handled very carefully during transpor-
tation and operation.
• If the positioner is used under
temperature outside of the specifica-
tion, the sealing materials deteriorate
quickly and also the positioner may
not operate normally.
• Use clean supply air fully removed
humidity and dust.
• If you leave the positioner at the
operation site for a long time without
using it, put the cover on it so that the
rain water does not enter the
positioner.
If the atmosphere is of high tem-
perature or high humidity, take mea-
sures to avoid condensation inside.
The condensation control measures
must be taken thoroughly for export
shipment.