Precision Digital Corporation PD687 User manual

MODEL PD687 31/2DIGIT EXPLOSION-PROOF
LOOP-POWERED METER
• 1 Volt Drop
•1″High Display
•Operates from -40 to 80°C
•Easy Calibration and
Installation
SPECIFICATIONS
Except where noted all specifications apply to operation at +25°C.
INPUT: 4-20 mA @ 24 VDC Maximum.
DISPLAY: 1.0″(25.4 mm) high LCD, ±1999.
CALIBRATION: Two-step; non-interacting zero and span.
CALIBRATION RANGE: 4 mA input: -1000 to +1000;
20 mA between 20 to 2000 counts > 4 mA display.
MAXIMUM VOLTAGE DROP: 1 VDC @ 20 mA.
ACCURACY: ±0.1% of span, ±1 count.
CONVERSION RATE: 2.5 conversions/second.
CONNECTIONS: Screw terminal block.
OPERATING TEMPERATURE RANGE: -40 to 80°C.
APPROVAL: The PD687-EX is FM Approved and CSA
Certified as explosion-proof for Class I, Division 1, Groups C
and D; dust-ignition proof for Class II, Division 1, Groups E,
F, and G; and Class III hazardous (classified) locations.
LCIE (CENELEC) certified as flameproof, EEx d IIB + H2 T6.
ENCLOSURE: Explosion-proof cast aluminum, 0.3% max.
copper content, NEMA 3, 4, 7, and 9, suitable for location in
Class I, Division 1, Groups B, C, & D and Class II, Groups
E, F, & G, Class III hazardous outdoor (Type 4X) locations.
CENELEC: EEx d IIB + H2 IP 66. One 3/4″NPT hole provided.
WARRANTY: 1 year parts and labor.
EXTENDED WARRANTY: May be extended an additional
12 months by returning the Product Registration Form within
2 months from date of purchase. Go to www.predig.com for
online registration.
DISCLAIMER: The information contained in this document
is subject to change without notice. Precision Digital 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.
Please visit the Precision Digital website at
www.predig.com
for complete information
on the entire line of Precision Digital products,
technical information and much more.
YOUR LOCAL DISTRIBUTOR IS:
ACTUAL SIZE DIGITS
Model Description
PD687 Loop-Powered Meter
in Explosion-Proof Enclosure
PD687-EX FM, CSA, & CENELEC
Explosion-Proof Meter
PDA6845 2″Pipe Mounting Kit (2 mounting holes)
PDA6545 2″Pipe Mounting Kit (4 mounting holes)
ORDERING INFORMATION
www.predig.com
PRECISION DIGITAL CORPORATION

MODEL PD687 31/2DIGIT EXP-PROOF LOOP-POWERED METER
Disassembly from the Enclosure
To access the Display PCB and Input Terminals it is necessary to
unscrew the enclosure cover and remove the two screws that hold the
display cover plate in place. Next, completely loosen the two screws
that hold the Display PCB and lift it out. The Display PCB and the
Input Signal PCB are connected together with 1 black and 1 red wire.
The wires are soldered to the Display PCB and connected to the Input
Terminal connector on the Input Signal PCB. Disconnect the black
and red signal wires from the Input Terminal connector and lift the
Display PCB from the enclosure (see Figure 1).
Servicing Display PCB Outside Loop
Two modes of input signal connections allow the user to remove the
Display PCB for service and maintain the loop connection. This is
done by connecting the LOOP JUMPER (see Figure 2) over both pins
of the header on the Input Signal PCB. The user may now operate the
Display PCB at another location by connecting a signal directly to the
“S+ and S-” wires on the Display PCB. When the display of the
instrument is put back in service the push-on LOOP JUMPER must
be removed from both pins, save the jumper by connecting it over one
pin only.
Figure 2. Control Loop Connected To Input Signal PCB
MOUNTING
Refer to Figure 3 for location of mounting holes located in each
corner of the enclosure. Mount the enclosure as desired and connect
the conduit to the 3/4
"
NPT hole provided. Install the Display PCB.
Figure 3. Dimensions and Mounting Information
WARNING: If any of the following operations are
performed in hazardous areas, all appropriate hazardous
area procedures must be followed.
WARNING: Disconnect from supply before opening.
Keep cover tight while circuits are alive. To prevent igni-
tion of group C atmospheres, all conduit runs must have a
sealing fitting connected within 3″of the enclosure.
AVERTISSEMENT: Ouvrir le circuit avant D’enlevel le
couvercle garder le couvercle bien fermé tant que les
circuits sont sous tension. Afin de prévenir l’inflammation
D’atmospheres de Classe I Groupe C, les courses de
conduit menant à ce boîtier doivent être connectées avec
des garnitures D’etanchéité approvées à une distance D’au
plus 3 pouces du boîtier.
WARNING: Calibration of the Loop-Powered Display
should be performed in a non-hazardous area prior to
installing it in its enclosure.
CAUTION: Care should be taken to avoid static electrici-
ty damaging the electronic circuitry.
SETUP
The only tools needed for calibration are a calibrated current source
and a screwdriver.
Decimal Point Selection
The decimal point jumper array is located in the lower right corner of
the Display PCB next to the display. It is labeled DP1, DP2, DP3.
Place a jumper over both pins of DP1 for a display of 199.9, DP2 for
19.99 or DP3 for 1.999.
Calibration
LO and HI calibration controls are located to the left of the display
(see Figure 1). Apply a signal equal to 4mA and adjust the LO con-
trol to display the desired reading. Apply a signal between 16 and 20
mA and adjust the HI control to display the desired reading.
Complete the calibration procedure by making any minor adjustments
to the LO and HI controls.
Figure 1. Assembly
LIM687 Rev C 02/02
INPUT SIGNAL PCB
NO CONNECTIONS
LOOP JUMPER
(remove when Display PCB is connected)
TRANSMITTER
HAZARDOUS AREA NON-HAZARDOUS AREA
POWER
SUPPLY
++
-
-
4-20mA
S+ S+S- S-
Field wiring is
made to the
Input Signal PCB
which is mounted
to the base of
the enclosure.
A: 6.34″(161 mm) C: 1.5″(38 mm) E: 5.13″(130 mm)
B: 5.13″(130 mm) D: 6.25″(159 mm) Weight: 8 lb (3.64 kg)
LO CAL
Display PCB
HI CAL
BAL
(Factory Adjust
Only)
DP 1
DP 2
DP 3
Input T rminal Conn ctor
Input Signal PCB
R d &
Black
Wir
Loop Jump r
Pollution D gr 2
Installation Cat gory II
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PRECISION DIGITAL CORPORATION
19 Strathmore Road • Natick MA • 01760 • USA • Tel: [phone] • Fax: [phone]