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PD420-461 4-20 mA Set Point Generator and Valve Positioner

PD420 Instruction Manual
PD420 Set Point Generator
PD421 NEMA 4X Set Point Generator
PD460 Valve Positioner
PD461 NEMA 4X Valve Positioner

Features

  • 4-20 mA Loop Set Point Generator
  • Panel Mount or NEMA 4X
  • 4-20 mA or 3-21 mA Output Ranges
  • Set Point Displayed as 0-100%, 4-20 mA, or 3-21 mA
  • Valve Position Displayed as 0-100%
  • Built-in Dial for Changing Output
  • Backlit Display
  • Coarse or Fine Set Point Adjustment
  • ± 0.5% Output Accuracy
  • 0.01 Display Accuracy
  • 15-30 VDC Power Requirement
  • < 500 ohms Sampling Resistance
  • Decals Provided for %, mA, Open, Closed, and Custom

Overview

The PD420/21 set point generator and the PD460/61 valve positioner provide a convenient way to generate a 4-20 mA signal that can be used to control another device.

Both feature a backlit LCD. The PD420/21 set point generator can be programmed to display 0-100%,
4-20 mA or 3-21 mA and output either 4-20 mA or 3-21 mA. The PD460/61 valve positioner is programmed to display a value of 0-100% relating to the 4-20 mA output. A built-in dial is provided to vary the displayed / output value. The dial may be programmed for coarse or fine adjustment.

The signal generator and valve positioner are both available as a panel mount or NEMA 4X version. In addition, NEMA 4X enclosures are provided to house up to three of the panel mount versions.

Decals are provided for %, mA, Open, and Closed for the user to apply to the faceplate. There is also a decal with a white background for the user to write a custom label.

Available Enclosures

The material for the enclosures is plastic and they are rated NEMA 4X. The enclosures will house models PD420 and PD460.

Connections

PD420-461 Powered by 24 VDC Supply

Set Point Generator / Valve Postioner
Powered by 24 VDC Supply

PD420-461 Powered by Control Device

Set Point Generator / Valve Postioner
Powered by Controlled Device

Dimensions Units: Inches (mm)


PD420/60 Panel Mount Dimensions

PD420 and PD460 Dimensions

Front View

PD420 and PD460 Dimensions

Back View

Notes:

  1. Panel cutout required: 3.0" x 1.6" (77 mm x 40 mm)
  2. Panel thickness: must be greater than 0.06" (1 mm)
  3. Mounting brackets snap in place for easy mounting


PD421/61 NEMA 4X Dimensions

PD421 and PD461 Dimensions

Front View

PD421 and PD461 Dimensions

Side View

Specifications

Output Accuracy: ± 0.5%
Output Ranges: 4-20 mA or 3-21 mA
Display: 0.3" (8 mm) high backlit LCD
Display Accuracy: 0.01
Display Modes: Current, 0-100%, 0-50.0 Hz
Display Change Adjustment: User may program coarse and fine adjustments such that each pulse on the dial results in a change of between 1 and 50 counts on the display.
Front Panel: NEMA 1 (PD420 and PD460)
Enclosure: NEMA 4X (PD421 and PD461)
Decals: (2 each): %, mA, Open, Closed, and white background for the user to write a custom label.
Operating Temperature Range: -4 to 140°F (-20 to 60°C)
Connections: Removable Screw Terminal Block
Power Requirement: 15-30 VDC
Sampling Resistance: Less than 500 Ω

Programming Instructions

Parameter Table 1:

Entering F002-F007 (FXXX System Settings) requires a password “+--+” first:

IndexDesignationComments
F001Output Mode0: Coarse tuning mode; use F004 to adjust increment value per click
1: Fine tuning mode; use F005 to adjust increment value per click
2: Quick output; use F100 to enter number of quick output settings
3: Automatic curve output: Use F200 to enter number of curves
F002Output Range0: 4-20 mA
1: 3-21 mA
F003Display Range0: Current
1: 0-100%
2: 0-50%
F004Coarse Tuning Increment Value1-50 Addition and subtraction for each click.
Disregard decimal point (1-50) x10
F005Fine Tuning Increment Value1-50 Addition and subtraction for each click.
Disregard decimal point (1-50) x10
F006Auto Save of Adjustment Value0: Not automatically saved. Need to press knob to save
1: Automatic save
F007CalibrationFactory set only
Default ValuesSet Point GeneratorValve Positioner
Coarse tuning modeIncrements of 0.10Increments of 1
Output range4-20 mA4-20 mA
Display mode4-20 mA0-100%

Change from coarse to fine tuning mode:

  1. Press and hold the knob for two seconds until F001 appears.
  2. Press the knob again
  3. Change the number from 0 (coarse tuning mode) to 1 (Fine tuning mode)
  4. Press the knob again

Entering Passwords:

  1. Rotate knob one click clockwise for “+”
  2. Rotate knob one click counter-clock for “-“
  3. Press the knob to confirm

Change the output range from 4-20 mA to 3-21 mA:

  1. Enter the password as described above
  2. The F002 menu is used to change the output range. Turn knob until the desired parameter number appears and press enter:
    a. 0: 4-20 mA
    b. 1: 3-21 mA
  3. Keep turning the knob until FEnd appears and press the knob to exit programming

Change the display from current (4-20 or 3-21 mA) to 0.0-100.0% or 0.0-50.0%:

  1. Enter the password as described above
  2. Turn the knob once clockwise and F003 appears.
  3. Press the knob and turn the knob until the desired parameter number appears and press enter:
    a. 0: Current
    b. 1: 0.0-100.0%
    c. 2: 0.0-50.0%
  4. Keep turning the know until FEnd appears and press the knob to exit

Change the value for how much each click on the knob adjusts coarse tuning:

  1. Enter the password as described above
  2. Turn the knob twice clockwise until F004 appears.
  3. Press the knob and turn the knob until the number that represents how much the display will change with each click appears and press enter.
  4. Keep turning the knob until FEnd appears and press the knob to exit

Change the value for how much each click on the knob adjusts fine tuning:

  1. Enter the password as described above
  2. Turn the knob three times clockwise until F005 appears.
  3. Press the knob and turn the knob until the number that represents how much the display will change with each click appears and press enter.
  4. Keep turning the know until FEnd appears and press the knob to exit

Change from pressing the knob to save programming to automatic save:

  1. Enter the password as described above
  2. Turn the knob four times clockwise until F006 appears.
  3. Press the knob and turn the knob until the desired parameter number appears and press enter:
    a. 0: Need to press knob to save programming
    b. 1: Automatic save
  4. Keep turning the know until FEnd appears and press the knob to exit

Parameter Table 2:

Entering F100... (Quick Output Settings) requires password “+-+-“ first

IndexDesignationComments
F100Number of quick settings0: Not used
2-9: Number of points
F101-109Output value of up to 9 pointsRange: 3.00-21.00 mA  (F100 must be > 0)

Programming Quick Output Points:

  1. Press and hold the knob for two seconds until F001 appears.
    a. Press the knob again
    b. Change the number from 0 (coarse tuning mode) to 2 (Quick Output Settings)
    c. Press the knob again to return to operation mode
  2. Press and hold the knob for two seconds until F001 appears.
    a. Enter password per instructions above to: +-+-
  3. Press the knob and F100 appears
    Adjust the knob until the desired number of Output Points appears and press the knob.
  4. Enter in Output Points
    a. F101 and value; enter all points

Parameter Table 3:

Entering F200... (Curve Output Settings) requires password “-+-+“ first

IndexDesignationComments
F200Number of curves0: Not used
1-9: Number of segments
Ft01Curve 1 run time0-999 seconds  (F200 must be > 0)
FA01Curve 1 start currentRange: 3.00-21.00 mA
Fb01Curve 1 end currentRange: 3.00-21.00 mA
Ft02Curve 1 run time0-999 seconds
Fb09Curve 1 end currentRange: 3.00-21.00 mA

Programming Curve Output Points:

  1. Press and hold the knob for two seconds until F001 appears.
    a. Press the knob again
    b. Change the number from 0 (coarse tuning mode) to 3 (Automatic curve output)
    c. Press the knob again to return to operation mode
  2. Press and hold the knob for two seconds until F001 appears. a.Enter password per instructions above to: -+-+
  3. Press the knob and F200 appears
    a. Press knob and enter the number of curves to be programmed
    b. Set Ft01: Run time for curve (0-999 seconds)
    c. Set FA01: Start current value (3.00 to 21.00 mA)
    d. Set Fb01: End current value (3.00 to 21.00 mA)
    e. Repeat for remaining curves

Examples of Automatic Curve Output Settings:

Curve settingF200=1 Ft01=10 FA01=4 Fb01=20
Curve settingF200=2 Ft01=10 Ft02=10 FA01=12 FA02=6 Fb01=12 Fb02=6
Curve settingF200=8 Ft01=2 Ft02=3 Ft03=3 Ft04=2 Ft05=2 Ft06=3 Ft07=3 Ft08=2 FA01=9 FA02=11 FA03=12 FA04=11 FA05=9 FA06=11 FA07=12 FA08=11 Fb01=11 Fb02=12 Fb03=11 Fb04=9 Fb05=11 Fb06=12 Fb07=11 Fb08=9
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