Precision Digital ISO 9001:2000 Certified Quality System

Setup	Calibration	Decimal Point Selection	Servicing Display

Dimensions	Specifications	Ordering Information	Documentation

FM & CSA LOOP-POWERED EXPLOSION-PROOF METERS

Features

4-20 mA Input
NEMA 4
1 V Drop
3½ Digit LCD 1" (25.4 mm) High
Operating Temperature Range: -40 to 80°C
¾" NPT Hole Provided

The PD687 can be installed just about anywhere in North America except Group A locations: indoors, outdoors, hot, cold, safe or hazardous area. The PD687-EX is FM Approved and CSA Certified as explosion-proof, will operate from –40 to 80°C, and adds only 1V to the loop. Its big 1 inch high display means it can be read from considerable distance. Calibration is a quick two-step process involving the adjustment of only two non-interacting potentiometers.

Note: For complete installation information see instruction manual linked below

Setup

The only tools needed for calibration are a calibrated current source and a screwdriver.

Figure 1: Assembly

Decimal Point Selection

The decimal point jumper array is located in the lower right corner of the Display Board 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 4 mA and adjust the LO control 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.

Servicing Display PCB Outside the Loop

Two modes of input signal connections allow the user to remove the Display Board 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 Board. The user may now operate the Display Board at another location by connecting a signal directly to the “S+ and S-” wires on the Display Board. 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 placing over one pin only.

Field wiring is made to the Input Signal Board which is mounted to the base of the enclosure.

Loop Powered Indicator PD687 Control Loop Connected To Input Signal Board

Figure 2: Control Loop Connected To Input Signal Board

Dimensions and Mounting Information

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 ¾" NPT hole provided and install sealing fittings

The user may mount the Display so conduit hole is oriented vertically or horizontally

Loop-powered Indicator Dimensions and Mounting Spec for PD687

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)

Figure 3

Specifications

General

Except where noted all specifications apply to operation at +25°C.

Input: 4-20 mA @ 24 VDC maximum
Display: 1.0" (25.4 mm) LCD, 3½ digits; 1999
Accuracy: ±0.1% FS ±1 count
Approvals: The PD687-EX is FM Approved & CSA Certified as explosion-proof for Class I, Division 1, Groups B, C, & D; dust-ignition proof for Class II, Division 1, Groups E, F, & G; and Class III hazardous (Classified) locations.
Enclosure: Explosion-proof cast aluminum with glass window, 0.3% max copper content, NEMA 4, 7, & 9, IP66; suitable for location in Class I, Division 1, Groups B, C, & D, Class II, Groups E, F, & G, Class III hazardous outdoor (Type 4) locations. One ¾" NPT hole provided.
Decimal Point: User selectable
Calibration: Two-step; non-interacting zero and span
Calibration Range: 4 mA input: -1000 to +1000;
20 mA input: between 20 and 2000 counts > 4 mA display
Display Update Rate: 2.5/second
Maximum Input Current: 30 mA
Maximum Voltage Drop: 1 V @ 20 mA
Operating Temperature: -40 to 80°C
Storage Temperature: -40 to 80°C
Relative Humidity: 0 to 90% non-condensing
Connections: Removable screw terminals accept 12 to 26 AWG
Conduit Hole: One ¾" NPT hole provided
Weight: 7.5 lb (3.4 kg)
Warranty: 2 years parts & labor
Extended Warranty: 1 or 2 years

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.

ORDERING INFORMATION Products
Model	Description	Price
PD687	Explosion-Proof Loop-Powered Meter	$569.00
PD687-EX	FM Approved & CSA Certified Explosion-Proof Loop-Powered Meter	$679.00

Accessories
Model	Description	Price
PDA6545	Zinc Plated Steel 4 Hole Pipe Mounting Kit	$99.00
PDA6845	Zinc Plated Pipe Mounting Kit with 2 Holes	$49.00
PDA6845-SS	Stainless Steel Pipe Mounting Kit with 2 Holes	$79.00
PDA-SSTAG	Stainless Steel Tag	$25.00

Documentation
The documentation can be downloaded from these links:

PD687: Instruction Manual

Mounting Kits for Precision Digital Meters

Setup and Calibration Services Order Form

Stainless Steel Tag Order Form

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