Protex PD6870 User manual

PD6870 Explosion-Proof Loop-Powered Process Meter
Instruction Manual
PRECISION DIGITAL CORPORATION
233 South Street • Hopkinton MA 01748 USA
Tel [phone] • Fax [phone]
www.predig.com
•Fully-Approved Explosion-Proof Loop-Powered Process Meter
•4-20 mA Input
•1 Volt Drop (4 Volt Drop with Backlight)
•1.0" (25.4 mm) 3½ Digits LCD Display; -1000 to 1999
•Display Mountable at 0°, 90°, 180°, & 270°
•HART®Protocol Transparent
•Loop-Powered Backlight Option
•Operating Temperature Range: -40 to 75°C (-40 to 167°F)
•Zero & Span Potentiometer Adjustments for Easy Field Scaling
•Conformal Coated PCBs for Dust and Humidity Protection
•FM Approved as Explosion-Proof / Dust-Ignition Proof / Flame-Proof
•CSA Certified as Explosion-Proof / Dust-Ignition Proof / Flame-Proof
•ATEX and IECEx Certified as Flame-Proof
•Wide Viewing Angle
•Flanges for Wall or Pipe Mounting
•Explosion-Proof, IP68, NEMA 4X Die-Cast Aluminum Enclosure
•Two 3/4" NPT Threaded Conduit Openings (One Plug Installed)
•2" U-Bolt Kits Available
•Stainless Steel Tag Available
•3-Year Warranty

PD6870 Explosion-Proof Loop-Powered Process Meter
Instruction Manual
2
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.
•Risk of electric shock or personal injury.
•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.
•Never remove the meter cover in explosive
environments when the circuit is alive.
•Cover must be fully engaged to meet
flameproof/explosion-proof requirements.
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.
© 2021 Precision Digital Corporation.
All rights reserved.
Introduction
The ProtEX-FarVu PD6870 is a rugged, explosion-
proof, loop-powered meter with 1" display digits ideal
for demanding applications in hazardous areas or in
the harshest environmental conditions. The meter
derives all of its power from the 4-20 mA loop with a
small 1 volt drop for easy installation in almost any
system.
The meter is programmed using four easy to access
front-mounted potentiometers with no complex or diffi-
cult to read programming menus necessary for setup.
The numeric display will read from -1000 to 1999 over
a 2000 count user adjustable scaling span. The back-
light option lets you see the display under any lighting
condition and is powered from the 4-20 mA loop with
no additional power supply required.
The enclosure is provided with two threaded conduit
holes and integrated pipe or wall mounting slotted
flanges.
Ordering Information
Model Description
PD6870-0L0 Explosion-Proof Loop-Powered
Process Meter
PD6870-0K0 Explosion-Proof Loop-Powered
Process Meter with Backlight
Accessories
Model Description
PDAPLUG75 3/4" Metal Conduit/Stopping Plug
PDA0001 3/4" M-NPT to F-M20 Reducer
PDA0002 3/4" M-NPT to 1/2" F-NPT Reducer
PDA1024-01 24 VDC Power Supply for DIN Rail
PDA6846
Steel 2" U-Bolt Kit. All Material: Zinc
Plated Steel; (1) U-Bolt for 2" Pipe with
(2 each) Washers, Lock Washers, and
Nuts.
PDA6846-SS
Stainless Steel 2" U-Bolt Kit. All
Material: Stainless Steel; (1) U-Bolt for
2" Pipe with (2 each) Washers, Lock
Washers, and Nuts.
PDA-SSTAG Custom Stainless Steel Tag (see
website for convenient ordering form)

PD6870 Explosion-Proof Loop-Powered Process Meter
Instruction Manual
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Accessories
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 provides a convenient way
to mount the PD6870 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.
Dimensions
Useful Tools
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 15-27 VDC wall plug is provided with the in-
strument. Optional USB power bank is available.

PD6870 Explosion-Proof Loop-Powered Process Meter
Instruction Manual
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Table of Contents
Introduction......................................................................................................... 2
Ordering Information.......................................................................................... 2
Accessories ........................................................................................................ 3
Specifications ..................................................................................................... 5
General............................................................................................................ 5
Input ................................................................................................................ 5
Product Ratings and Approvals.................................................................... 6
Electromagnetic Compatibility...................................................................... 6
Safety Information.......................................................................................... 6
Installation........................................................................................................... 7
Unpacking....................................................................................................... 7
Pre-Installed Conduit Plug ............................................................................ 7
Mounting ......................................................................................................... 7
Dimensions..................................................................................................... 7
Cover Jam Screw ........................................................................................... 8
Connections ................................................................................................... 8
Wiring Diagrams............................................................................................. 8
Setup ................................................................................................................... 9
Overview ......................................................................................................... 9
Scaling Controls and Display........................................................................ 9
Setting Up the Meter ...................................................................................... 9
Setting the Decimal Point............................................................................. 9
Minimum & Maximum Input Span............................................................ 9
Calibrating the Meter.................................................................................... 9
Factory Default & User Settings.................................................................. 10
Troubleshooting ............................................................................................... 10
Troubleshooting Tips................................................................................... 10
EU Declaration of Conformity.......................................................................... 11
Table of Figures
Figure 1. Enclosure Dimensions – Front View................................................... 7
Figure 2. Enclosure Dimensions – Side Cross Section View ........................... 7
Figure 3. Connector Board .................................................................................. 8
Figure 4. Connections without Backlight ........................................................... 8
Figure 5. Connections with Loop-Powered Backlight....................................... 8

PD6870 Explosion-Proof Loop-Powered Process Meter
Instruction Manual
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Specifications
Except where noted all specifications apply to operation at +25°C.
General
Display 3 ½ digit LCD
1" (25.4 mm); -1000 to 1999
Display
Orientation
Display may be mounted at 90° increments
up to 270° from default orientation.
Display
Update Rate
2.5 Updates/Second
Backlight White; Loop-powered. Backlight can be
enabled or disabled via alternative wiring of
terminal block. Loop-powered backlight
brightness will increase as the input signal
current increases.
Display
Overrange
Display reads 1 on the left most digit
Programming
Method
Four (coarse and fine for zero and span)
potentiometers accessed when the cover is
removed.
Recalibration Recalibration is recommended at least every
12 months.
Normal Mode
Rejection
60 dB rejection ratio
Environmental
Operating temperature range: -40 to 75°C
Storage temperature range: -40 to 75°C
Relative humidity: 0 to 90% non-condensing
Printed circuit boards are conformally coated.
Connections Screw terminals accept 12 to 22 AWG wire
Enclosure
NEMA 4X, IP68 Explosion-proof die cast
aluminum, 0.30% max copper content,
corrosion resistant epoxy coating,
Color: Blue
Window: Glass
Two ¾" NPT threaded conduit openings.
One ¾" NPT nickel plated brass conduit plug
with 12 mm hex key fitting installed.
Mounting May be mounted directly to conduit.
Two slotted flanges for wall mounting or
NPS 1½" to 2½" or DN 40 to 65 mm pipe
mounting. See Dimensions on page
7.
Overall
Dimensions
5.65" x 5.25" x 4.86" (W x H x D)
(144 mm x 133 mm x 124 mm)
Weight 5.00 lbs (80 oz, 2.27 kg)
Warranty 3 years parts and labor. See Warranty
Information and Terms & Conditions on
www.predig.com for complete details.
Input
Input 4-20 mA
Accuracy
±0.1% of full span ±1 count
Maximum
Voltage Drop &
Equivalent
Resistance
Without
Backlight
With Loop-Powered
Backlight
1 VDC @ 20 mA 4 VDC @ 20 mA
50 Ω @ 20 mA 200 Ω @ 20 mA
Temperature
Drift
150 PPM/°C from -40 to 75°C ambient
Decimal Point
User selectable decimal point
Calibration
Range
4 mA input: -1000 to +1000;
20 mA between 20 and 2000 counts
greater than 4 mA display.
Two point linear display span.
Input Overload
Over current protection to 2 A max.
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.

PD6870 Explosion-Proof Loop-Powered Process Meter Instruction Manual
6
Product Ratings and Approvals
FM
Explosion-proof for use in:
Class I, Division 1, Groups B, C and D
Dust-ignition proof for use in:
Class II/III, Division 1, Groups E, F and G; T6
Flame-proof for use in:
Class I, Zone 1, AEx d Group IIC; T6
Protection by Enclosure:
Zone 21, AEx tb IIIC; T85°C
Ta = -40 to 75°C.
Enclosure: Type 4X, IP66.
Certificate number: 3040391
CSA
Explosion-proof for use in:
Class I, Division 1, Groups B, C and D
Dust-ignition proof for use in:
Class II/III, Division 1, Groups E, F and G; T6
Flame-proof for use in:
Zone 1, Ex d IIC T6
Ta = -40 to 75°C.
Enclosure: Type 4X & IP66/IP68.
Certificate number: 2325749
ATEX
II 2 G D. Flame-proof for use in:
Zone 1, Ex d IIC T6 Gb
Protection by Enclosure for use in:
Dust Atmospheres (Zone 21)
Ex tb IIIC T85°C Db IP68.
Ta = -40°C to +75°C
Certificate number: Sira 10ATEX1116X
IECEx Flame-proof for use in:
Zone 1, Ex d IIC T6 Gb
Protection by Enclosure for use in:
Dust Atmospheres (Zone 21)
Ex tb IIIC T85°C Db IP68.
Ta = -40°C to +75°C
Certificate number: IECEx SIR 10.0056X
Special Conditions for Safe Use:
Use suitably certified and dimensioned cable entry
device and/or plug. The equipment shall be installed
such that the supply cable is protected from mechani-
cal damage. The cable shall not be subjected to ten-
sion or torque. If the cable is to be terminated within
an explosive atmosphere, then appropriate protection
of the free end of the cable shall be provided.
Year of Construction:
This information is contained within the serial number
with the first four digits representing the year and
month in the YYMM format.
For European Community: The PD6870 must be
installed in accordance with the ATEX directive
2014/34/EU, and the product certificate Sira
10ATEX1116X.
Electromagnetic Compatibility
Emissions EN 61326-1
Safety requirements for measurement,
control, and laboratory use – Industrial
Group 1 Class A ISM emissions
requirements
Radiated
Emissions
Class A
Immunity EN 61326-1
Safety requirements for measurement,
control, and laboratory use
ESD ±4 kV contact,
±8 kV air
RFI –
Amplitude
Modulated
80-1000 MHz @ 10 V/m,
1.4-2.0 GHz @ 3 V/m,
2.0-2.7 GHz @ 1 V/m,
80% AM (1 kHz)
EFT ±2 kV DC mains, ±1 kV other
Telco Surge ±1 kV
CRFI 3 V, 0.15-80 MHz, 1 kHz 80% AM
Safety Information
•Read complete instructions prior to installation
and operation of the meter.
•Installation and service should be performed only
by trained service personnel. Service requiring
replacement of internal components must be
performed at the factory.
•Disconnect from supply before opening
enclosure. Keep cover tight while circuits are
alive. Conduit seals must be installed within 18"
(450mm) of the enclosure.
•Verify that the operating atmosphere of the meter
is consistent with the appropriate hazardous
locations certifications.
•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.

PD6870 Explosion-Proof Loop-Powered Process Meter Instruction Manual
7
Installation
For Installation in USA:The PD6870 must be in-
stalled in accordance with the National Electrical
Code (NEC) NFPA 70.
For Installation in Canada:The PD6870 must be in-
stalled in accordance with the Canadian Electrical
Code CSA 22.1. All input circuits must be derived
from a CSA approved Class 2 source.
For European Community: The PD6870 must be in-
stalled in accordance with the ATEX directive
2014/34/EU and the product certificate Sira
10ATEX1116X.
•Installation and service should be performed only
by trained service personnel. Service requiring
replacement of internal components must be
performed at the factory.
•Disconnect from supply before opening
enclosure. Keep cover tight while circuits are
alive. Conduit seals must be installed within
18" (450mm) of the enclosure.
All controls and wiring connections are located on the
display module that is accessed by removing the en-
closure cover. The controls can be accessed without
removing the display module. The wiring connections
can be accessed by removing the display module
which is secured to the enclosure by two captive
screws.
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.
Pre-Installed Conduit Plug
The PD6870 is supplied with one pre-installed conduit
plug for installations that do not require the use of
both conduit entries. The conduit/stopping plug in-
cludes an internal hexagonal socket recess for
removal. The conduit plug and its factory installation
are included in all hazardous area approvals of this
product.
•In hazardous areas, conduit and conduit/stopping
plugs require the application of non-setting
(solvent free) thread sealant. It is critical that all
relevant hazardous area guidelines be followed for
the installation or replacement of conduit or plugs.
Mounting
The PD6870 has two slotted mounting flanges 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 1 and Figure 2.
•Do not attempt to loosen or remove flange bolts
while the meter is in service.
Dimensions
All units: inches (mm)
Figure 1. Enclosure Dimensions – Front View
Figure 2. Enclosure Dimensions –
Side Cross Section View
Note: The supplied conduit plug may extend up to 0.6
in [15 mm] from the conduit opening when installed.
3.35 (85.1)
2.25 (57.1)
5.25 (133.4)
(143.5)
5.65
(8.2)
0.32
3.35 (85.0)
4.15 (105.5)
3.22 (81.9) (123.5)
4.86

PD6870 Explosion-Proof Loop-Powered Process Meter Instruction Manual
8
Cover Jam Screw
The cover jam screw should be properly installed
once the meter has been wired and tested in a safe
environment. The cover jam screw is intended to
prevent the removal of the meter cover in a flame-
proof environment without the use of tools. Using a
M2 hex wrench, turn the screw clockwise until the
screw contacts the meter. Turn the screw an
additional 1/4 to 1/2 turn to secure the cover.
Caution: Excess torque may damage the threads
and/or wrench.
Connections
To access the wiring connections, remove the enclo-
sure cover and unscrew the two captive screws that
fasten the display module. Signal connections are
made to a three-terminal connector on the rear of the
display module. Grounding connections are made to
the two ground screws provided on the base – one in-
ternal and one external.
S+
4-20 mA signal positive terminal
connection
S-
4-20 mA signal return/negative terminal
connection
B-
4-20 mA signal return/negative terminal when
using the installed loop-powered backlight op-
tion.
Refer to Figure 3 for terminal positions.
•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.
•Use proper grounding procedures/codes.
•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.
Figure 3. Connector Board
Wiring Diagrams
Signal connections are made to a three-terminal con-
nector mounted on the rear of the display module.
The enclosure also provides one internal and one ex-
ternal earth grounding screw.
The 4-20 mA input with no backlight has a maximum
voltage drop of 1 V and is wired as shown in Figure 4.
The loop-powered backlight configuration requires a
total maximum voltage drop of 4 V. The backlight op-
tion is recommended for dim lighting conditions and is
enabled when wired as shown in Figure 5.
Figure 4. Connections without Backlight
Figure 5. Connections with Loop-Powered Backlight

PD6870 Explosion-Proof Loop-Powered Process Meter Instruction Manual
9
Setup
Overview
Setting the 4-20 mA input for the desired display is
done using a calibrated 4-20 mA signal source and
the four potentiometers located on the front of the dis-
play module. The cover must be removed to access
these potentiometers. There is also a jumper array for
setting the decimal point.
Scaling Controls and Display
Control Description
LO 4 mA display adjust.
LO FINE 4 mA precision display adjust.
HI 20 mA display adjust.
HI FINE 20 mA precision display adjust.
Setting Up the Meter
Setting the Decimal Point
A decimal point may be set using a three-position
jumper array located on the rear of the display
module. To access the jumper array, unscrew the
two captive screws that fasten the display module.
Remove the display module and place the jumper on
the desired pins as indicated on the board for decimal
point locations of D.DDD, DD.DD, DDD.D, or remove
it if no decimal point is desired.
Minimum & Maximum Input Span
A minimum input span of 20 counts is required be-
tween the 4 mA and 20 mA inputs. A maximum input
span of 2000 counts may be setup between the 4 mA
and 20 mA input.
The meter will not calibrate properly if these minimum
and maximum span ranges are not maintained during
scaling.
Calibrating the Meter
The meter is provided factory calibrated to display
-50.0 at 4 mA and 150.0 at 20 mA.
Apply a 4 mA signal and adjust the LO potentiometers
(coarse and fine) to display the desired reading. Apply
a signal between 16 and 20 mA and adjust the HI po-
tentiometers (coarse and fine) to display the desired
reading. Complete the calibration procedure by mak-
ing minor adjustments to the LO and HI fine potenti-
ometers as necessary.

PD6870 Explosion-Proof Loop-Powered Process Meter Instruction Manual
10
Factory Default & User Settings
The following table shows the factory setting for most
of the programmable parameters on the meter. Next
to the factory setting, the user may record the new
setting for the particular application.
Model: ____________________________________
S/N: ______________________________________
Date: _____________________________________
Parameter Default Setting User Setting
Decimal
point
1 place
Calibration
Settings
Input 1 4.00 mA
Display 1 -50.0
Input 2 20.00 mA
Display 2 150.0
Troubleshooting
The rugged design and the user-friendly interface of
the meter should make it unusual for the installer or
operator to refer to this section of the manual. If the
meter is not working as expected, refer to the recom-
mendations below.
Troubleshooting Tips
Symptom Check/Action
No display Check input signal connections.
Display unsteady
during calibration
Adjust LO FINE or HI FINE con-
trols to fine-tune the display.
Meter displays 1on
the left most digit
location
Check signal level is not over
range.
Dial down the HI control and re-
calibrate at 20 mA.
Display is faded Check input signal is not under
1 mA.
Backlight does not
appear
Verify backlight is installed.
Check signal connections are
as shown in Figure 5on page 8.
Other symptoms
not described
above
Call Technical Support for
assistance.

EU Declaration of Conformity
Issued in accordance with ISO/IEC 17050-1:2004 and ATEX Directive 2014/34/EU.
We,
Precision Digital Corporation
233 South Street
Hopkinton, MA 01748 USA
as the manufacturer, declare under our sole responsibility that the product(s),
Model PD6870 Series Loop Powered Meter
to which this declaration relates, is in conformity with the European Union Directives shown below:
2014/35/EU Low Voltage Directive
2014/34/EU ATEX Directive
2014/30/EU EMC Directive
2011/65/EU RoHS Directive
This conformity is based on compliance with the application of harmonized or applicable technical stand-
ards and, when applicable or required, a European Union notified body certification.
Standards:
EN 60079-0:2009
EN 60079-1:2007
EN 60079-31:2009
EN 61010-1:2001
EN 61326:2006
The standards EN 60079-0:2009, EN 60079-1:2007, EN 60079-31:2009, EN 61010-1:2001, and EN
61326-1:2006 are no longer harmonized. The requirements of these standards have been checked
against the harmonized standard EN 60079-0:2018, EN 60079-1:2014, EN 60079-31:2014, EN 61010-
1:2010+A1:2019, and EN 61326-1:2021 and there were no major technical changes affecting the latest
technical knowledge for the products listed above.
EC Type Examination Certificate: Sira 10ATEX1116X
Product Markings: II 2 G D
Ex d IIC T6 Gb
Ex tb IIIC T85°C Db IP68
Tamb = -40°C to +75°C
ATEX Notified Body for EC Type Examination Certificate: CSA Group Netherlands B.V., NB 2813
Utrechtseweg 310
6812 AR, Arnhem, Netherlands
ATEX Quality Assurance Notification No.: SIRA 10 ATEX M462
ATEX Notified Body for Quality Assurance: CSA Group Netherlands B.V., NB 2813
Utrechtseweg 310
6812 AR, Arnhem, Netherlands
Signed for and on behalf of Precision Digital Corporation:
Name: Jeffrey Peters
Company: Precision Digital Corporation
Title: President
Date: June 16, 2021 Document No: DoC PD6870 {061621}

PD6870 Explosion-Proof Loop-Powered Process Meter Instruction Manual
PRECISION DIGITAL CORPORATION
233 South Street • Hopkinton MA 01748 USA
Tel [phone] • Fax [phone]
www.predig.com
LIM6870_K
06/21
Contact Precision Digital
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Email: [email protected]
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