Precision Digital Corporation PD6908 User manual

PD6908 Loop-Powered Process Meter
Instruction Manual
PRECISION DIGITAL CORPORATION
233 South Street • Hopkinton MA 01748 USA
Tel [phone] • Fax [phone]
www.predig.com
•Loop-Powered Field-Mount Process Meters
•4-20 mA Input Displayed with ±0.02% of Full-Scale Accuracy
•1.5 Volt Drop (4.7 Volt Drop with Backlight)
•0.7" (17.0 mm) 5 Alphanumeric Characters Top Display
•0.4" (10.2 mm) 8 Alphanumeric Characters Bottom Display
•20-Segment Bargraph Standard
•Display Mountable at 0°, 90°, 180°, & 270°
•CapTouch Through-Window Button Programming with Normal and Delayed Modes
•Loop-Powered Backlight with Red Backlight for Alarm Conditions
•(2) Open Collector Outputs Standard; Assignable to Pulse, Alarm, Timer, or Stopwatch
•(2) Optional Loop-Powered Solid-State Relays; Assignable to Alarm, Control, Timer, or Stopwatch
•Stopwatch & Timer Functions to Drive Relays & Open Collectors
•Optional Isolated 4-20 mA Analog Output
•Relay Pump Alternation Based on Level and Runtime
•Display Relay Runtime & Cycle Count via Relay Info Menu
•Round Horizontal Tank Function; Just Enter Diameter & Length
•32-Point Linearization, Square Root Extraction andProgrammable Exponent Function
•Free PC-Based MeterView XL USB Programming Software
•Enable and Disable Backlight from Menu
•Operating Temperature Range: -40 to 75°C (-40 to 167°F)
•Conformal Coated PCBs for Dust & Humidity Protection
•Password Protection
•Flange for Wall or Pipe Mounting; Loop for Stainless Steel Tag; Holes for Tamper-Proof Seal
•Plastic NEMA 4X, IP66 Enclosure
•Three 3/4" NPT Threaded Conduit Openings (Two Plugs Included)
•3-Year Warranty
MeterView XL
USB Install

PD6908 Loop-Powered Process Meter
Instruction Manual
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The Complete PD6900 Series
Plastic Enclosures - General Purpose
PD6907-GP-PL
4-20 mA Input
Feet & Inches Meter
PD6908-GP-PL
4-20 mA Input
Process Meter
PD6928-GP-PL
4-20 mA Input
Flow Rate/Totalizer
PD6938-GP-PL
Pulse Input
Flow Rate/Totalizer
Aluminum Enclosures - Hazardous Area Approved
PD6907-HA-AL
4-20 mA Input
Feet & Inches Meter
PD6908-HA-AL
4-20 mA Input
Process Meter
PD6928-HA-AL
4-20 mA Input
Flow Rate/Totalizer
PD6938-XX-AL
Pulse Input
Flow Rate/Totalizer
Stainless Steel Enclosures - Hazardous Area Approved
PD6907-HA-SS
4-20 mA Input
Feet & Inches Meter
PD6908-HA-SS
4-20 mA Input
Process Meter
PD6928-HA-SS
4-20 mA Input
Flow Rate/Totalizer
PD6938-XX-SS
Pulse Input
Flow Rate/Totalizer

PD6908 Loop-Powered Process Meter
Instruction Manual
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Table of Contents
Introduction..........................................................................................................6
Key Features ........................................................................................................7
Ordering Information.........................................................................................11
Accessories ...................................................................................................11
Specifications.....................................................................................................13
Display............................................................................................................13
General...........................................................................................................13
Enclosure.......................................................................................................14
Input................................................................................................................14
Common Open Collector & Relay Specifications.......................................14
Open Collector Outputs................................................................................14
Solid-State Relays .........................................................................................15
4-20 mA Transmitter Output.........................................................................15
On-Board Digital Input..................................................................................15
MeterView XL Software.................................................................................15
Compliance Information....................................................................................16
Electromagnetic Compatibility.....................................................................16
EU Declaration of Conformity...........................................................................16
Safety Information .............................................................................................16
Installation..........................................................................................................17
Unpacking......................................................................................................17
Conduit Plugs Included ................................................................................17
Mounting ........................................................................................................17
Dimensions....................................................................................................17
Connections.......................................................................................................18
Display & Options Modules..........................................................................18
Connectors Labeling.....................................................................................19
Wiring Diagrams ................................................................................................21
Current Loop (4-20 mA) Connections .........................................................21
Digital Input Connections ............................................................................21
4-20 mA Output Connections......................................................................21
Solid-State Relay Connections....................................................................21
Open Collector Output Connections............................................................22
Remote Operation of Meter.........................................................................22
Setup and Programming...................................................................................23
Overview.........................................................................................................23
CapTouch Buttons ........................................................................................23
CapTouch Buttons Delay ............................................................................23
Turning Off CapTouch Buttons....................................................................23
CapTouch Button Tips & Troubleshooting ..................................................23
MeterView XL Programming Software.........................................................24
CapTouch Buttons and Status Indicators...................................................25
Display Functions & Messages....................................................................26
Main Menu......................................................................................................30
Setting Numeric Values...............................................................................31
Scaling the 4-20mAInput (INPUT)...................................................................32
Available Unit Classes and Units ................................................................33
Setting Custom Units (CUSTOM)..................................................................34
Setting the Display Features (DISPLAY).....................................................34
Changing the Engineering Units (UNITS)...................................................34
Changing the Decimal Point (DEC.PT).........................................................34
Enabling or Disabling Commas on the Bottom Display (COMMA)................35
Display Capabilities Optimization (TOP and BOTTOM) ................................35
Configuring the Display (TOp and BOTTOM)................................................36
Programming the Bargraph (BARGRAPH)....................................................37

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Programming the Outputs (OUTPUT)...........................................................37
Open Collector Outputs ( OPEN COLLECTR ) .................................................38
Solid-State Relay Outputs (RELAY) ............................................................43
Isolated 4-20 mA Output (4-20 mA) ..........................................................49
Output Manual Control (CONTROL).............................................................49
Advanced Features Menu (ADVANCE)..........................................................50
Advanced Process Variable Setup (ADV PV SETUP) ...............................51
Low-Flow Cutoff (CUTOFF)..........................................................................58
Noise Filter (FILTER) .................................................................................58
Enabling Password Protection (PASSWRD) .................................................58
Programmable Function Keys User Menu (USER)......................................59
Tare (TARE).................................................................................................60
Changing System Settings (SYSTEM).........................................................61
Meter Operation .................................................................................................63
CapTouch Buttons Operation ......................................................................63
CapTouch Buttons ........................................................................................63
CapTouch Button Tips & Troubleshooting ..................................................63
Function Keys Operation..............................................................................64
Digital Input Operation..................................................................................64
Maximum/Minimum Readings......................................................................64
Runtime & Cycle Count (INFO)....................................................................64
Changing Engineering Units........................................................................64
Troubleshooting.................................................................................................65
Reset Meter to Factory Defaults...................................................................65
Determining Software Version.....................................................................65
Factory Default Settings..............................................................................66
Troubleshooting Tips....................................................................................67

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Table of Figures
Figure 1. Enclosure Dimensions –Front View....................................................17
Figure 2. Enclosure Dimensions –Side View .....................................................17
Figure 3. Enclosure Dimensions –Top View ......................................................17
Figure 4. Connector Labeling for PD6908-GP-PL-LNN.......................................19
Figure 5. Connector Labeling for PD6908-GP-PL-L2N.......................................19
Figure 6. Connector Labeling for PD6908-GP-PL-L3N.......................................20
Figure 7. Connector Labeling for PD6908-GP-PL-L5N.......................................20
Figure 8. 4-20 mA Input Connection without Backlight .....................................21
Figure 9. 4-20 mA Input Connection with Backlight...........................................21
Figure 10. Digital Input Connections ...................................................................21
Figure 11. 4-20 mA Output Connections .............................................................21
Figure 12. Solid-State Relay Connections...........................................................21
Figure 13. Open Collector Output Connections..................................................22
Figure 14. PDA2361-R Control Station Connected to PD6928...........................22
Video
Watch the Loop-Powered Meters Video
Click or Scan

PD6908 Loop-Powered Process Meter
Instruction Manual
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Disclaimer
The information contained in this document is
subject to change without notice. Precision Digital
Corporation makes no representations or
warranties with respect to the contents hereof;
and specifically disclaims any implied warranties
of merchantability or fitness for a particular
purpose.
•Read complete instructions prior to installation
and operation of the meter.
•This product is not recommended for life support
applications or applications where malfunctioning
could result in personal injury or property loss.
Anyone using this product for such applications
does so at his/her own risk. Precision Digital
Corporation shall not be held liable for damages
resulting from such improper use.
•Failure to follow installation guidelines could
result in death or serious injury. Make sure only
qualified personnel perform the installation.
WARNING
Cancer and Reproductive Harm - www.P65Warnings.ca.gov
Limited Warranty
Precision Digital Corporation warrants this
product against defects in material or
workmanship for the specified period under
“Specifications” from the date of shipment from
the factory. Precision Digital’s liability under this
limited warranty shall not exceed the purchase
value, repair, or replacement of the defective unit.
See Warranty Information and Terms &
Conditions on www.predig.com for complete
details.
Registered Trademarks
All trademarks mentioned in this document are
the property of their respective owners.
© 2023 Precision Digital Corporation.
All rights reserved.
Introduction
The PD6908 VantageView+ loop-powered process
meter can be installed in a variety of harsh operating
environments to provide convenient and informative
display of any 4-20 mA signal. One of the most
convenient features of these instruments is their
dual-line display which is typically used to display the
process variable on the 5-character alphanumeric top
display and the units of measure or a tag on the
8-character alphanumeric bottom display. Another
common setup is to display the input in one scale on
the top display (such as feet) and in another scale on
the bottom display (such as gallons). The top display
uses 12-segment, and the bottom display uses
14-segment alphanumeric characters for clear
indication of tags, units, or alarm messages.
Further enhancing the display on these instruments is
a 20-segment bargraph.
These loop-powered meters can be installed virtually
anywhere because they get their power from the
4-20 mA loop and therefore require no separate
power source. And they only drop 1.5 V (4.7 V with
backlight), so they add very little burden to the loop.
Additional features that allow these instruments to be
installed virtually anywhere include a NEMA 4X, IP66
plastic enclosure, an operating temperature range of
-40 to 167°F (-40 to 75°C), conformally coated PCBs,
and a backlit LCD that can be read in bright sunlight
or dimly lit areas.
Free, PC-based, MeterView XL software that
connects to the meter via a micro USB cable is
available for programming and setup of the meters.
For more details, see the MeterView XL manual. Four
CapTouch through-window buttons are available to
operate the instrument without removing the cover.
All models come equipped with two open collector
outputs and a digital input. There are also models
available with two solid-state relays and isolated
4-20 mA analog output options. The open collector
outputs are useful for alarm indication. The digital
input can be used to acknowledge the relays, to
start/stop a timer/stopwatch, and more. The relays
can be programmed for alarm indication, on/off
control, or pump alternation.

PD6908 Loop-Powered Process Meter
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Key Features
2X More Informative Display
The PD6908 display offers a 50% larger display area
and is twice more informative than previous
generations of loop-powered meters. Featuring an
alphanumeric dual-line display and a 20-segment
bargraph, reading and understanding process values
is easy and intuitive. The addition of status indicators
provides a quick glance at alarm conditions, relays,
process trends, and more. Predefined display units
give users even more display flexibility. Plus, the high
contrast backlit LCD display is readable from far away
and under various lighting conditions.
Backlight Turns Red on Alarm
When an alarm occurs, the display can be
programmed to turn red, flash, and display an alarm
indicator . In addition, a unique custom alarm
message for each of the two relays and two open
collectors can be displayed on the bottom display.
These features can be activated even if no relay or
open collector is connected.
CapTouch Through-Window
Buttons
The PD6908 is equipped with four capacitive sensors
that operate as through-window buttons so that it can
be operated without removing the cover (and
exposing the electronics) in a harsh operating area.
CapTouch buttons are designed to work under any
lighting condition and to protect against false
triggering. They can be disabled for security via a
switch on the display module.
CapTouch buttons have two modes of operation:
Normal and Delayed. Delayed mode prevents
accidental trigger of the buttons. In the Delayed
mode, the buttons enter into a low sensitivity state
(sleep) and they ignore quick button presses after 20
seconds of inactivity. To wake up the buttons, press
and hold any button for more than 2 seconds, the
buttons respond normally.
Solid State Relays 1-2
Indicators
Predefined
Display Units
0.7" (17.0 mm) High
5-Character, Alphanumeric
12-segment
Password Protection
Process Trend
Indicators
CapTouch Buttons
Self-Calibration
0.4" (10.2 mm) High
8-Character, Alphanumeric
14-segment
Two-Color
Backlight
Alarm Indicator
20-Segment
Bargraph
CapTouch Buttons /
Function Keys

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Instruction Manual
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Wide Viewing Angle
The window and display module have been optimized
to provide a wide viewing angle of approximately
±40°; nearly twice that of the competition. Plus, the
display module can be rotated in 90° increments
providing added mounting flexibility.
Dual-Scale Feature
Users can use the dual-scale feature to display the
input in two different scales. For instance, the
example above shows an application where the
display shows the input in feet and gallons while the
display toggles between process values and units.
Predefined and Custom Units
The meter has six available preprogrammed unit
classes: volume, height, temperature, pressure,
weight, and rate. When the desired unit class or unit
of measure within a class is not available, a custom
unit may be programmed.
14-Segment Characters
Notice how much better letters like “T”, “N” and “K”
appear as14-segment characters on the bottom display
vs. 7-segment characters found on other meters.
Password Protection
A password can be set up for programming security to
prevent unauthorized changes to the programmed
parameter settings.
Enable / Disable Backlight
The backlight may be enabled or disabled using the
System - Backlight menu. The backlight is enabled by
default, but the input must be wired appropriately for
the backlight to function. See Enabling or Disabling
the Backlight (BACKLITE) on page 62 for details.
Multiple Outputs
•Two open collector outputs (standard)
•Two solid-state relays (optional)
•One 4-20 mA output (optional)
The open collector outputs and relays generally
operate in the same manner, with the major exception
being the open collectors are not available for pump
alternation and the relays are not available with pulse
features. The open collectors and relays can be
controlled either automatically or manually.
The isolated analog output signal can be configured
to represent the process variable (PV1, PV2, or
retransmit). It can also be reverse scaled such that
the meter’s high calibration value outputs 4 mA and
the meter’s low calibration outputs 20 mA.
Free MeterView XL
Programming Software
The fastest and easiest way to program the meter is
using the free Meterview XL programming software.
This software greatly simplifies the programming
process and allows the user to save configuration files
for later use.
The meter connects to the PC via a provided micro-
USB cable and is powered by the USB connection, so
no additional power is needed during programming.
Easy Wiring & Service
The PD6908 has been designed for easy wiring and
servicing. All connections are made to removable
screw terminal blocks. There are no exposed printed
circuit boards.

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Instruction Manual
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Modern and Practical Enclosure
The PD6908 NEMA 4X, IP66 plastic enclosure
provides serious protection from the elements, high
impact, corrosion, dust, etc.
Built-In Flange for Pipe Mounting
The built-in mounting flange allows easy mounting to
walls or pipes.
A slot on the back makes it easy to center the unit on
a pipe. There are three ¾" NPT threaded conduit
holes for wiring. Two ¾" NPT plastic conduit plugs are
included.
SS Tag Attaching Loop
The enclosure is also equipped with a loop at the top
to easily attach a PDA-SSTAG stainless steel tag.
Tamper-Proof Capability
The instrument can be made tamper-proof by
inserting a wire through the built-in loop on the base
of the enclosure and a hole in the lid of the enclosure
and securing this wire with a lead seal.

PD6908 Loop-Powered Process Meter
Instruction Manual
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Pump Alternation
The PD6908 can be used as a pump controller to
alternate two pumps and indicate high and low alarm
conditions. The pumps can be programmed to
alternate on level and runtime and the display can be
programmed to turn red and flash a message on
alarm conditions. The meter can display the pump
runtimes and the number of times they have cycled.
See the Pump Control with Alternation & Alarm
Example on page 47 for full details.
Relay #2 turns the main pump on at 6000 gallons and
turns it off at 1000 gallons. lights up to show relay
2 is energized. The indicates level is rising.
With the Pump Alternation feature activated, the next
time the level reaches 6000 gallons, relay #1 transfers
and starts the backup pump. lights up to show
relay 1 is on.
Input Signal Conditioning
To satisfy applications that require scaling in ways
other than the usual 2-point linear method, the
PD6908 can also be scaled for square root (DP flow),
programmable exponent (open channel flow) or round
horizontal tank volume calculation.
Round Horizontal Tank
Linearization
This function automatically calculates the volume in a
round horizontal tank with flat ends and allows that
reading to be displayed on the bottom display. This
results in a meter that displays the height of the tank
on the top display and volume on the lower display.
The user only needs to enter the diameter and length
of the tank and the meter takes care of the rest.
Square Root Linearization
The square root function can be used to linearize the
signal from a differential pressure transmitter and
display flow rate in engineering units.
Programmable Exponent
Linearization
The programmable exponent can be used to linearize
the signal from level transmitters in open-channel flow
applications using weirs and flumes.

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Ordering Information
General Purpose Instruments
VantageView+ PD6908 • Decimal Models • Plastic Enclosure
Model
Description
PD6908-GP-PL-LNN
Loop-Powered Field-Mount Process Meter, No Options
PD6908-GP-PL-L2N
Loop-Powered Field-Mount Process Meter, Two Solid-State Relays
PD6908-GP-PL-L3N
Loop-Powered Field-Mount Process Meter, 4-20 mA Analog Output
PD6908-GP-PL-L5N
Loop-Powered Field-Mount Process Meter, Two Solid-State Relays & 4-20 mA Analog Output
Notes:
1. All models come with bargraph, two open collector outputs, and one digital input standard.
2. All models come standard with three ¾" NPT conduit holes and two plastic conduit plugs.
Accessories
Model
Description
PD659
Signal Isolators, Splitters, and Conditioners
PD9501
Multi-Function Calibrator
PD9502
Low-Cost Signal Generator
PDA1002
6" DIN Rail Mounting Kit
PDA1024-01
24 VDC Transmitter Power Supply for DIN Rail
PDA6846
Steel 2" U-Bolt Kit. All Material: Zinc Plated Steel; (1) U-Bolt for 2" Pipe with (2) Washers,
(2) Lock Washers, and (2) Nuts
PDA6846-SS
Stainless Steel 2" U-Bolt Kit. All Material: Stainless Steel; (1) U-Bolt for 2" Pipe with (2) Washers,
(2) Lock Washers, and (2) Nuts
PDAPLUG75P
3/4" Plastic Conduit Plug (Two Plugs Included with Meter)
PDA-SSTAG
Custom Stainless Steel Tag (see website for convenient ordering form)
PDA-BUTTON
Momentary Pushbutton
PDA2360 Plastic Control Stations
Model
Description
PDA2360-E
Emergency Button
PDA2361-A
Ack Button
PDA2361-B
Blank Button
PDA2361-R
Reset Button
PDA2361-T
Tare Button
PDA2361-S
Stop Button
PDA2361-Q
Silence Button
Note:
Control stations can be connected directly to the meter’s Digital
Input terminals labeled DI+ and DI-. See Remote Operation of
Meter on page 22 for details.
Signal Splitter & Conditioner Accessories
Model
Description
PD659-1MA-1MA
Signal Isolator with One 4-20 mA
Input and One 4-20 mA Output
PD659-1MA-2MA
Signal Splitter with One 4-20 mA
Input and Two 4-20 mA Outputs
PD659-1V-1MA
Signal Conditioner with One 0-10
VDC Input and One 4-20 mA Output
PD659-1MA-1V
Signal Conditioner with One
4-20 mA Input and One 0-10 VDC
Output

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PDA1024-01 24 VDC Power Supply
The PDA1024-01 is a DIN rail mounted 1.5 A,
24 VDC power supply that can be used to power
the 4-20 mA transmitter.
PDA6846 2"U-Bolt Kits
The PDA6846 U-Bolt Kits provide a convenient way to
mount the meter to 1.5" or 2" pipes. They are
available in steel and stainless steel.
PDA-SSTAG Stainless Steel Tag
The PDA-SSTAG is a laser etched stainless steel tag
that can be customized with three lines of text.
Each tag comes with a stainless steel wire and lead
seal for easy mounting wherever you need.
PD9501 Multi-Function Calibrator
This PD9501 Multi-Function Calibrator has a variety
of signal measurement and output functions, including
voltage, current, thermocouple, and RTD.
PD9502 Low-Cost Signal Generator
The PD9502 is a low-cost, compact, simple to use
4-20 mA or 0-10 VDC signal generator. It can easily
be set for 0-20 mA, 4-20 mA, 0-10 V or 2-10 V
ranges. Signal adjustment is made with a one-turn
knob. A wall plug is provided with the instrument.
Optional USB power bank is available.

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Specifications
Except where noted all specifications apply to operation at +25°C.
Display
Display
Dual-line LCD with backlight.
Both lines: alphanumeric
Top: 0.7" (17.8 mm) 5 digits, 12-segment
Bottom: 0.4" (10.2 mm) 8 characters,
14-segment
Display may be programmed to turn red and
flash a user-defined message on
alarm condition.
On-Screen
Indicators
See CapTouch Buttons and Status Indicators
on page 25 for details.
Top Display
5 digits (-9999 to 99999) or 5 characters
Bottom
Display
8 digits (-9,999,999 to 99,999,999; separated
by commas) or 8 characters
(all capital & most lower-case letters)
Backlight
Powered by 4-20 mA loop
Intensity varies with signal level
Bargraph
20 segments
Decimal Point
Up to four decimal places on top display and
up to seven decimal places on bottom display
Commas
Commas to indicate 1000s
(e.g. 88,987,628) on the bottom display only
Dual-Scale
Feature
The input can be displayed in different scales
on the top and bottom displays. For instance,
the top display could display the input in
height units and the bottom display could
show that same input in volume units.
Alarm
Indication
Programmable: loop-powered red backlight,
flashing display, alarm symbol , bargraph
segment flashes on alarm.
Custom
Alarm
Messages
Programmableforeachrelay/opencollector:
8charactersmaximum;displayedevery10secfor
1seconbottomdisplay.Maybeturnedoff.
Display
Update Rate
Ambient > -10°C: 1 Update/Second
Ambient = -20°C: 1 Update/2 Seconds
From -20°C to -40°C the update rate slows
down 1 second for every -2°C
(e.g. at -24°C, 1 update/4 seconds).
Overrange
Top: 99999; Bottom: 99,999,999 (flashing)
Underrange
Top: -9999; Bottom: -9,999,999 (flashing)
General
Programming
Method
Four CapTouch through-window buttons
when cover is installed. The CapTouch
buttons can be used with the cover removed.
Free PC-based USB MeterView XL
programming software.
Environmental
Operating temperature range:
-40 to 75°C (-40 to 167°F)
Storage temperature range:
-40 to 85°C (-40 to 185°F)
Relative humidity: 0 to 90% non-condensing
Printed circuit boards are conformally coated
Noise Filter
Averages the input signal over a period of
time between 1 and 16 seconds to dampen
the effects of a noisy signal that causes a
jumpy display.
Filter Bypass
0.0 to 99.9% of full scale. Input signal
changes that are greater than the bypass
value are displayed immediately.
Recalibration
Recalibration is recommended at least every
12 months.
Max / Min
Display
Max / min readings reached by the process
are stored until reset by the user or until
power to the meter is turned off.
Tare
Tare function zeros out the meter to remove
the weight of a container.
Tare function can be assigned to a function
key or the digital input.
Password
Programmable password restricts
modification of programmed settings.
Non-Volatile
Memory
All programmed settings are stored in non-
volatile memory for a minimum of ten years if
power is lost.
Normal Mode
Rejection
64 dB at 50/60 Hz
Connections
Removable screw terminal blocks
Display terminals: accept 16 to 30 AWG wire
Relay terminals: accept 12 to 26 AWG wire
4-20 mA output: accept 16 to 30 AWG wire
Tightening
Torque
Display terminals: 2.5 lb-in (0.28 Nm)
Relay terminals: 4.5 lb-in (0.5 Nm)
4-20 mA output terminals: 2.5 lb-in (0.28 Nm)
Overall
Dimensions
5.25" x 5.65" x 4.18" (133 x 144 x 106 mm)
(W x H x D)
Weight
1.9 lbs (0.9 kg)
Warranty
3 years parts and labor. See Warranty
Information and Terms & Conditions on
www.predig.com for complete details.

PD6908 Loop-Powered Process Meter
Instruction Manual
14
Enclosure
Material
Polycarbonate plastic with UV stabilizer
Gasket
Buna-N
Rating
NEMA 4X, IP66 plastic, UL 94V-0
Color
Gray
Window
Clear polycarbonate with UV stabilizer
Conduits
Three ¾" NPT threaded conduit openings
Conduit
Stopping
Plug
Two ¾" NPT plastic conduit plugs with 1.29"
wrenching flats and a screwdriver slot are
included
Flange
Built-in flange for wall and pipe mounting.
Tamper-Proof
Seal
Enclosure lid may be secured with
tamper-proof seal.
Instrument
Tag Loop
Built-in loop for securing stainless steel tag
Overall
Dimensions
5.25" x 5.65" x 4.18" (133 x 144 x 106 mm)
(W x H x D)5.25" x 5.65" x 4.18" (133 x 144 x
106 mm) (W x H x D)
Weight
1.4 lbs (0.64 kg)
Input
Input
4-20 mA
Accuracy
±0.02% of span ±1 count,
Square root and programmable exponent:
10-100% FS
Voltage Drop
Without backlight: 1.5 V maximum,
With backlight: 4.7 V maximum
Equivalent
Resistance
Without backlight: 75 Ω @ 20 mA
With backlight: 235 Ω @ 20 mA
Input
Overload
Over current protection to 1 A maximum,
Over voltage protection to 30 VDC max
(Between mA+ and mA- / BL-)
Temperature
Drift
25 PPM/°C from -40 to 75°C ambient
Function
PV1: Linear (2-32 points), square root, or
programmable exponent
PV2: Linear (2-32 points) or round horizontal
tank
Low-Flow
Cutoff
0.1 to 999,999 or disable. Point below at which
the display always shows zero.
HART
Transparency
The meter does not interfere with existing
HART communications; it displays the
4-20 mA primary variable and it allows the
HART communications to pass through
without interruption. The meter is not affected if
a HART communicator is connected to the
loop. The meter does not display secondary
HART variables.
Common Open Collector &
Relay Specifications
Number
Two open collectors & two relays
High or Low
Alarm
User programmable for high or low alarm
Alarm
Deadband
0-100% FS, user programmable
Output
Assignment
Alarm, Timer, Stopwatch, or Disable
Alarm Output
Source
Assign to PV (PV1, PV2) or Digital Input
On & Off Time
Delay
0 to 9,999 seconds
Fail-Safe
Operation
Independent for each open collector and
relay.
Fail-safe on, the output is on under normal
conditions.
Fail-safe off, the output is on under alarm
conditions.
Alarm
Operation
Automatic, automatic with manual override,
latching (manual reset anytime), latching with
reset after cleared (manual reset only after
alarm has cleared)
Alarm
Indication
Programmable: loop-powered red backlight,
flashing display, alarm symbol , bargraph
segment flashes on alarm.
Custom
Alarm
Messages
Programmableforeachrelay/opencollector:
8charactersmaximum;displayedevery10secfor
1seconbottomdisplay.Maybeturnedoff.
Alarm
Acknowledge
CapTouch ACK button or external digital
input resets output and screen indication.
Auto
Initialization
When power is applied to the meter, open
collectors and relays will reflect the state of
the input to the meter.
Timer Output
One-shot or Continuous
Off Time Delay: 1 sec to 99:59:59
(hrs:min:sec)
On Time: 1 sec to 99:59:59 (hrs:min:sec)
Stopwatch
Output turns on when started and off when
stopped.
Open Collector Outputs
Rating
Isolated open collector, sinking NPN
5-30 VDC @ 150 mA maximum
Output
Assignment
Pulse, Alarm, Timer, Stopwatch, or Disable
Pulse Output
Source
PV (PV1, PV2) or Test Frequency
Pulse Output
Factor
0.000001 to 999,999.9
Pulse Width
0.5 ms @ 1 kHz; 500 ms @ 1 Hz;
50% duty cycle
Pulse Output
Frequency
1,000 Hz maximum
Quadrature
Pulse Output
Available for Output 2
(90° behind Output 1) 500 Hz max
Alarm Output
Source
Assign to PV (PV1, PV2)
or Digital Input

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Instruction Manual
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Solid-State Relays
Rating
250 VAC/VDC @ 0.5 A resistive
38 VA; 250 VAC; 0.3 A pilot duty
(inductive)
13 VA; 250 VDC; 0.3 A pilot duty (inductive)
Noise
Suppression
Metal oxide varistors across outputs
Relay
Assignment
Pump Alternation, Alarm, Timer, Stopwatch
on/off, or Disable
Alarm Output
Source
Assign to PV (PV1, PV2) or Digital Input
Pump
Alternation
Relays may be programmed to alternate with
each pump cycle with an elapsed time
override where the pumps will alternate
regardless of level. Pump alternation time
can be programmed for 0 to 999:59 (hrs:min)
Relay (Pump)
Runtime
Meter will keep track of how long each relay
(pump) has operated and display this
information.
Relay (Pump)
Cycles
Meter will keep track of how many times the
relays (pumps) have cycled and display this
information.
4-20 mA Transmitter Output
Accuracy
±0.05% FS ±0.001mA
Output
Source
PV1, PV2, re-transmit; reverse scaling
allowed
Scaling
Range
1.00 to 23.0 mA
Disable
High impedance state, less than 1 mA
Calibration
Factory calibrated 4.00 to 20.00 mA
Underrange
1.0 mA, 3.5 mA, or 3.8 mA
(If input < 3.5 mA); or Off; user selectable
Overrange
20.5 mA, 20.8 mA, or 23.0 mA
(If input > 20.5 mA); or Off; user selectable
Isolation
500 V input-to-output
Temperature
Drift
0.5 µA/°C max from -40 to 75°C ambient
External Loop
Power Supply
7.0 VDCto30.0 VDCmaximum
Output Loop
Resistance
10-750 Ω @ 24 VDC; 10-1100 Ω @ 30 VDC
On-Board Digital Input
Function
Remote acknowledge/reset relays, reset
max/min values, etc. See User section of
Display Functions & Messages on page 26
for a complete list of capabilities.
Contacts
2.1 VDC on contact. Connect normally open
contacts across DI+ and DI-
Logic Levels
Logic High: 2.4 to 30 VDC (max)
Logic Low: 0 to 0.9 VDC
MeterView XL Software
Availability
Free download from www.predig.com
System
Requirements
Microsoft®Windows®7 & 10
Communicati
ons
USB 2.0 (Standard USB A to Micro USB B)
Cableprovided
Configuration
Configure all parameters on the meter.
Configure meters one at a time.
Configuration
Files
Generate with or without meter connected;
Save to file for later use.
USB Power
Connection
Meter is powered by USB connection during
programming, if 4-20 mA loop is not
connected.
Compatibility
Programs created for Loop Leader and Loop
Leader+ may be run on either meter.
Programs created for VantageView+ and
ProtEX+ can be run on either meter. No other
program sharing is permissible.
To download the latest MeterView XL programming
software and manual, visit predig.com/meterviewxl.

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Compliance Information
Electromagnetic Compatibility
EMC Emissions
•CFR 47 FCC Part 15 Subpart B Class A
emissions requirements (USA)
•ICES-003 Information Technology
emissions requirements (Canada)
•AS/NZS CISPR 11 Group 1 Class A
ISM emissions requirements
(Australia/New Zealand)
•EN 55011 Group 1 Class A ISM
emissions requirements (EU)
•EN 61000-6-4 Emissions requirements
for Heavy Industrial Environments -
Generic
EMC Emissions
and Immunity
EN 61326-1 EMC requirements for
Electrical equipment for measurement,
control, and laboratory use –industrial use
EU Declaration of
Conformity
For shipments to the EU and UK, a Declaration of
Conformity was printed and included with the product.
For reference, a Declaration of Conformity is also
available on our website www.predig.com/docs.
Safety Information
•Read complete instructions prior to installation
and operation of the meter.
•Hazardous voltages exist within enclosure.
Installation and service should be performed only
by trained service personnel.
•Service requiring replacement of internal
components must be performed at the factory.
•Control room equipment must not use or
generate more than 250 VRMS or VDC.
•PD6908 Series Loop-Powered meters do not add
capacitance or inductance to the loop under
normal or fault conditions.
•Equipment contains non-metallic materials and
therefore special care and consideration should
be made to the performance of these materials
with respect to chemicals which may be present
in a harsh operating environment.

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Instruction Manual
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Installation
To access the connectors, remove the enclosure
cover and unclip the display module by pulling it from
the enclosure. The display module may be
disconnected from the options module to facilitate
wiring to the options module.
Unpacking
Remove the meter from box. Inspect the packaging
and contents for damage. Report damages, if any,
to the carrier.
If any part is missing or the meter malfunctions,
please contact your supplier or the factory for
assistance.
Conduit Plugs Included
The PD6908 is supplied with two plastic conduit plugs
for installations that do not require the use of all three
conduit entries.
Mounting
The PD6908 has a slotted mounting flange that may
be used for pipe mounting or wall mounting.
Alternatively, the unit may be supported by the
conduit using the conduit holes provided. Refer to
Figure 1and Figure 2.
•Do not attempt to loosen or remove flange bolts
while the meter is in service.
Dimensions
Figure 1. Enclosure Dimensions –Front View
Figure 2. Enclosure Dimensions –Side View
Figure 3. Enclosure Dimensions –Top View
5.25" (133 mm)
3.35" (85.1 mm)
2.25"
(57.2 mm) 0.32"
(8.2 mm)
5.65"
(144 mm)
4.18"
(106 mm)

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Instruction Manual
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Connections
To access the connectors, remove the enclosure cover and unclip the display module by pulling it from the enclosure.
Signal, backlight, open collector, and digital input connections are made to removable connectors on the display
module. Relays and 4-20 mA output connections (if installed) are made to removable connectors on the options
module mounted in the base of the enclosure. The display module may be disconnected from the options module to
facilitate wiring to the options module.
•Observe all safety regulations. Electrical wiring should be performed in accordance with all agency
requirements and applicable national, state, and local codes to prevent damage to the meter and ensure
personnel safety.
•Static electricity can damage sensitive components.
•Observe safe handling precautions for static-sensitive components.
•If the meter is installed in a high voltage environment and a fault or installation error occurs, high voltage may
be present on any lead or terminal.
Display & Options Modules
The display module snaps into built-in rails on the enclosure ensuring a secure and perfect fit every time. No tools are
needed to install or remove it. The options module is screwed into the base of the enclosure. Both modules
completely encase the printed circuit boards.
Options Board (Left) and Display Module (Right)
Options Board Connected to Display Module
Options Board Mounted on the Bottom of Enclosure
Display Module Mounted on Built-In Rails

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Instruction Manual
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Connectors Labeling
The following graphics show the locations of the connectors for each available configuration.
Figure 4. Connector Labeling for PD6908-GP-PL-LNN
Figure 5. Connector Labeling for PD6908-GP-PL-L2N
USB
Connection
CapTouch
On/Off
Switch
Ribbon Cable
Connector
–+
OC2
–+
OC1
Open Collector
Outputs
DI BL mA
–+–+–
Digital
Input
Backlight
+ Signal
Options Board
USB
Connection
CapTouch
On/Off
Switch
Ribbon Cable
Connector
–+
OC2
–+
OC1
Open Collector
Outputs
NO
CNO
C
Solid State
Relay 2
Solid State
Relay 1
DI BL mA
–+–+–
Digital
Input
Backlight
+ Signal

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Figure 6. Connector Labeling for PD6908-GP-PL-L3N
Figure 7. Connector Labeling for PD6908-GP-PL-L5N
Options Board
USB
Connection
CapTouch
On/Off
Switch
Ribbon Cable
Connector
–+
OC2
–+
OC1
Open Collector
Outputs
4-20 mA
Output
+
–
DI BL mA
–+–+–
Digital
Input
Backlight
+ Signal
Options Board
USB
Connection
CapTouch
On/Off
Switch
Ribbon Cable
Connector
–+
OC2
–+
OC1
Open Collector
Outputs
NO
CNO
C
Solid State
Relay 2
Solid State
Relay 1
4-20 mA
Output
+
–
DI BL mA
–+–+–
Digital
Input
Backlight
+ Signal