DATEL, Inc., Mansfield, MA 02048 (USA)

• Tel: (508)339-3000, (800)233-2765 Fax: (508)339-6356 • Email:sales@datel.com • Internet: www.datel.com

4-20mA Current Loop

Application Board for

DMS-30LCD Meters

DMS-EB-LP

Features

••••• Loop-powered, no external

supply required

••••• Includes gain (span) and offset (zero)

adjustments

••••• Range and decimal point settings are

DIP-switch selectable

••••• Covers hundreds of different ranges

••••• Reliable screw-terminal connections

••••• Low cost

Ordering Information

DMS-EB-LP

Current loop board

DMS-BZL1

Bezel assembly

DMS-BZL2

Bezel assembly with

sealing gasket

Full Scale Input

4mA to 20mA

Voltage Drop

7.5V, maximum

Input Resistance

550

Ω, nominal

Accuracy

±0.05%FS ±1 count

Operating Temperature Range

0 to +60°C

Temperature Drift

±100ppm/°C, typical

Storage Temperature Range

–20 to +75°C

Humidity

0 to 95%, non-condensing

Dimensions

2.02" (51.31mm)L x 0.83" (21.08mm)W

TB1 Wire Size and Strip Length:

18 to 26 AWG (solid or stranded)

Strip Length

0.20" (5.08mm)

Functional Specifications

Figure 1. DMS-EB-LP Schematic Diagram

Actual Size

Description: The DMS-EB-LP was specifically designed for 4-to-20mA current-loop

process-monitoring applications. The board simply mounts onto the rear of a DMS-

30LCD-1-5, allowing both the application board and the meter to be powered solely from

the 4-to-20mA loop input. Align pin 1 of the board with pin 1 of the DMS-30LCD-1-5 and

simply solder the two assemblies together.

Features: Gain (span) and offset (zero) adjustments are both performed using precision,

22-turn potentiometers. Decimal point selections and range changes are all made on an

eight-position DIP switch featuring gold-plated contacts — there are no cumbersome

jumpers or solder gaps to contend with! Connections to the loop are made via a reliable,

screw-type terminal block. The only assembly tool required is a screwdriver!

Applications: The DMS-EB-LP's design accommodates hundreds of different display

reading combinations. This essentially

eliminates the need to order "specials" in

applications in which several different-

range meters are required. OEM

customers should consider using

DATEL's new DMS-30LCD-4/20S which

already has the DMS-EB-LP soldered to

a rugged DMS-30LCD-1-5 digital

voltmeter.

Technical Notes

DP3

DP2

DP1

(–) INPUT LO

(+) INPUT HI

ANALOG

COMMON

REF. IN

+5V

SUPPLY

V–

GND

V+

CAP–

CAP+

R1

90.9

R4

2.21k

R7

2k

Gain Adjust

C3

2.2µF, 10V

D2

RLZ5231

C1

2.2µF

10V

2

1

4

5

3

8

U1

LOOP

RETURN

LOOP

INPUT

–

+

4-20mA

R5

698

R2

2.94k

TB1

2

1

R6

90.9

RJ4

0

R9

10.5

5

6

7

8

1

2

3

4

R12

5k

D1

LM4041

R10

10k

C2

2.2µF

10V

ON

R8

26.7

R3

5k

Zero Adjust

BOOST

12

11

8

7

10

9

3

4

5

6

2

1

5V

RETURN

SW1

®®

12

TB1

R3

Zero

Adjust

R7

Gain

Adjust

C2

SG10

+–

TB2

2

1

U1

C1

C3

D2

SW1

D1

R10

R6

R9

R8

R1

SG9

RJ4

5

6

7

8

1

2

34

ON

R12

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