LASCAR DPM342 User Manual

DPM 342 LED Backlit 4-20mA Loop Powered Indicator

A compact loop powered indicator giving an accurate, zero corrected indication of 4-20mA loop current. Calibration is by two multi-turn
potentiometers which allow sensitive adjustment of the instrument. The DPM 342 features an integral snap-in bezel, making installation
easy. The module’s LED backlighting ensures a clear display, even under low light conditions. No soldering is required. Connection to the
current loop is via two screw terminals. The correct decimal point is selected via a jumper link.

11mm (0.43“) Digit Height

Programmable Decimal Points

Low Volt Drop

Loop Powered

LED Backlighting

Simple Screw Terminal Connections

Wide Adjustment Range

Auto-polarity on Display

Stock Number

Standard Meter DPM 342

Specification Min. Typ. Max. Unit

Accuracy (overall error) * 0.05 0.1 %(±1 count)
Linearity ±1 count
Sample rate 3 samples/sec
Operating temperature range 0 50 °C
Temperature s 200 ppm/°C
Loop Volt Drop 5 5.6 6 V
Supply current 4 mA
Full scale reading (20mA) 0 1999 Count
Offset adjustment range -950 +950 Count

*To ensure maximum accuracy, re-calibrate periodically.

tability

+ (span x 0.25)

CONNECTOR SOURCING GUIDE

METHOD Screw Terminals - No Connector Required

DIMENSIONS All dimensions in mm (inches)

40.0 (1.57)

27.3 (1.07)

12.7 (0.50)

20.0 (0.79)

17.5 (0.69)

37.5 (1.48)

WEBSITE: http://www.lascarelectronics.com/

abc

d

a. 2.00 (0.08)
b. 6.00 (0.24)
c. 1.60 (0.06) max
d. 9.50 (0.37)

DP3

DP2

Panel cut-out

38.0 x 18.0 (1.50 x 0.71)

Panel thickness

1.0 to 2.5 (0.04 to 0.1)

REAR VIEW

LK1

CAL

DP1

ON BOARD JUMPER LINKS

OFF

+-+ -

Calibration potentiometers

LASCAR ELECTRONICS LTD.

MODULE HOUSE, WHITEPARISH,

TEL: [phone] FAX: [phone]

WILTSHIRE SP5 2SJ UK

E-mail: [e-mail]

LASCAR ELECTRONICS INC.

3750 West 26th Street,

TEL: [phone] FAX: [phone]

Erie, PA 16506 USA

E-mail: [e-mail]

LASCAR ELECTRONICS (HK) LIMITED

FLAT C, 5/FL., LUCKY FTY. bldg., 63-65 HUNG TO ROAD

KWUN TONG, KOWLOON, HONG KONG

TEL: [phone] FAX: [phone]

E-mail: [e-mail]

TERMINAL FUNCTIONS

1. + Positivecurrentinput.

-

2. Negative currentinput.

CALIBRATION

The meterissuppliedcalibratedtoread000 for 4mA loop current and 1000 for 20mA. C because theDPM342
has a very wide adjustment range . Place the jumper link across LK1. This disables the offset adjustment to enable span adjustment to be made first.
After span adjustment is complete, the jumper link is removed and the offset adjustment is made. The jumper link is then used to display one of the
decimal pointsifnecessary.

Example tore-calibrate:Meter toread -40.0for4mA and150.0 for20mA.

1. Calculate thespan bysubtracting thedesired reading at4mA fromthe desiredreading at 20mA: -1500 -(-400) = 1900

2. Short jumperlink Lk1with thelink header normallyused toselect the desiredDecimal Point.
Link Lk1 islocated abovethe screwterminals.

3. Apply 16mAbetween the+ and- screw terminals.

4. Adjust the CALpotentiometer sothe DPM342 indicates 1900.

5. Remove jumperlink Lk1and placeit back onthe desiredDecimal Point (DP1 inthis case).

6. Apply 4mAbetween

7. Adjust the OFFpotentiometer sothe DPM 342indicates thedesired reading at4mA: -40.0

8. Adjust CAL andOFF asnecessary for optimumaccuracy,by repeating steps2 to 7.

the - and+ screwterminals.

alibration iscarried outin two simple stages

SAFETY

The usermust ensurethat theincorporation ofthe DPMinto theuser’s equipmentconforms tothe relevantsections ofBS EN 61010 (Safety Requirements for
Electrical Equipment forMeasuring, Controland Laboratory Use). No inputsother than 4-20mA indicatingloop current should be made.

JUMPER LINKS: In order to quickly and easily select the

required Decimal Point, themeter has several on-boardjumper links.

DP3

DP2

DP1

PANELFITTING

DP3

DP2

DP1

Locate the meter by passing it through the front of the panel cut-out and gently push until the rear of the bezel is flush with
the panel (DO NOT PUSH ON THE LCD). The snap-in lugs will now automatically hold the meter firmly in position. Take
care when inserting the meter, not to damage the current loop wires and not to short them on the panel.

DP3

DP2

DP1

CURRENT LOOP CONNECTION: The DPM 342 and

its backlighting are powered from the 4-20mA signal loop and need no
other power supply. Ensure correct polaritywhen connecting.

I+

4-20mA

Transmitter

Connecting the DPM 342 to a 4-20mA Current Loop.

I-

+

DPM 342

-

Specifications liable to change without prior warning DPM 342 Issue 3 August/2002 S.P.W. Applies to DPM 342/1