LASCAR DPM500S User Manual

DPM 500S 3½ Digit LCD Module

The DPM 500S uses advanced components and construction techniques to provide a uniquely compact unit. The meter is in a 40 pin DIL
integrated circuit formatthat can bepluggeddirectly into aDILsocket or panelmountedusing the snapin bezel. For single railuse, the DPM
500S features abuiltin negative railgenerator, enablingthemeter to measureasignal referenced toitsown power supply0V.

12.5mm (0.5“) Digit Height

Programmable Decimal Points

°°

Auto-zero

Auto-polarity

200mV d.c. Full Scale Reading (F.S.R.)

Annunciators

+

-

CF

µA

mV

kΩ

MHz

SCALING

Two resistors Ra andRb may befitted in orderto alter the
full scale reading(F.S.R.) ofthe meter - see table.
Meter will needre-calibration.

Required F.S.R. Ra Rb

2V Note 910k 100k
20V Note 1M 10k
200V Note 1M 1k
2kV Note 1M 100R
200 A 0R 1k

µ

2mA 0R 100R
20mA 0R 10R

Single Rail Version DPM 500S

Specification Min. Typ. Max. Unit

Accuracy (overall error)* 0.05 0.1 % (±1 count)
Linearity ±1 count
Sample rate 3 sample/sec
Operating temperature range 0 50 °C
Temperature stability 100 ppm/°C
Supply voltage 3.5 5 6.5 V
Supply current 250 A
Input leakage current (Vin = 0V) 1 10 pA

* To ensure maximum accuracy, re-calibrate periodically.

Stock Number

µ

200mA 0R 1R

NOTE

Ensure link 10is cutif fitting Ra.

CONNECTOR SOURCING GUIDE

METHOD 40 Pin DIL IC Socket

SAFETY

To comply with the Low Voltage Directive (LVD 93/68/EEC), input voltages to the module’s pins must not exceed 60Vdc. If voltages to the
measuring inputs do exceed 60Vdc, then fit scaling resistors externally to the module. The user must ensure that the incorporation of the
DPM into the user’s equipment conforms to the relevant sections of BS EN 61010 (Safety Requirements for Electrical Equipment for
Measuring, Control andLaboratory Use).

DIMENSIONS All dimensions in mm (inches)

1.1

8.2

(0.04)

60.0 (2.36)

30.0 (1.18)

(0.32)

45.0 (1.77)

16.0 (0.63)

Display in TEST mode

PANELFITTING

Fit the bezel to the front of the panel
and locate the meter into the bezel
from behind. Alternatively the meter
and bezel may be assembled before
fitting to the front of the panel but care
must be taken not to use excessive
force. Finally fit the window into the
front of the bezel.

1

40

1.87

(0.07)

52 (2.05)

7

V

m

°F

°C

V+

Ω

HI

Hz

TEST

REF

LO

REF

REF+

0.5

(0.02)

V+

K

~

M

BG

-5V

REF-

COM

XDP

IN HI

IN LO

2.54
(0.1)

12

µ

A

20

:

-

E3

AB

XB3

POL

21

15.2 (0.60)

V-

DP1

DP2

DP3

24.8 (0.98)

BP

XG3

4.80 (0.19)

4.0 (0.16)6.7 (0.26)

9

11

1

13

12

10

Rb Ra

40

12

7

5

3

2

4

1

7

20

8

15

14

21

ON-BOARD LINKS

OPTIONAL SCALING
RESISTORS

REAR VIEW

Panel cut-out = 57 x 27 (2.24 x 1.06)

www.lascarelectronics.com

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]

PIN FUNCTIONS

1, 40. V+ Positive powersupply.
2 -7, 12-14, 17, 38, 39 See

15. - Inputforthepolarityannunciator. Internally linked to POL (pin 20). If thisis tobeexternallycontrolled,cutlink11.

16, 18, 19, 22 XB3, E3, AB, XG3. Outputs for usein auto-rangingapplications.

20. POL Drive for "-" annunciator. Internally connectedby link11.

21. BP LCDbackplane drivewaveform.

23. DP3 1.999

24. DP2 19.99 See

25. DP1 199.9

26. V- Negative power supply. Note thatthe voltagebetweenV+andV-must notexceed6.5V.

27. XDP Connect to required annunciators/DPs(seenote).

28. -5V Outputfromnegativerailgeneratorcircuit. This output is an inversion of V+.

29. BG Input for bandgap reference.(1.22V nom).

30. INLO Negative measuring input. Analogue inputs must be no closer than 1V to either thepositive ornegative supply. The negative

31. INHI Positivemeasuringinput. supply of the DPM500S isgenerated internallyandmirrors the positive supply voltage.

32. COM Thegroundfortheanaloguesectionofthe A/D converter, held actively at 2.8V (nom) below V+. COM mustnot beallowedtosink

33. REF- Negativeoutputfrominternalreference.

34. REF+ Positiveoutput frominternalreference.

35. REF LO Negative inputfor referencevoltage.

36. REF HI Positiveinput forreference voltage.

37. TEST Connecting thispintoV+turns on the segments as illustrated. It shouldnot beoperated formore thanafewsecondsastheDC

40. V+/CLK NormallytiedtoV+viaLink12butcan be used to over ride the internal oscillatorand controlthe sampleratebycuttingLink12and

SPECIAL NOTE: ANNUNCIATORS.

SPECIAL NOTE: ANNUNCIATORS.

excessivecurrent(> 100 A) by connecting it directly to a highervoltage.

µ

voltage applied to the LCD may "burn" thedisplay. This pin is nominally at 5V below V+ and is theground forthe digitalsection
of the meter, it can be used as anegative supplyto powerexternallogicuptoamaximumof1mA.

making Link 13.

SPECIAL NOTE: ANNUNCIATORS:

The DPM annunciators (DPs, °C, etc.) can be displayed by connecting them to XDP. However as these
annunciators are normally ‘floating’, under certainconditions they may appear when not wanted. To suppressunwanted annunciators, link themto
the backplane (BP). If the annunciators are being switched, connect them via a 1M resistor to the BP (pin 21). The annunciators will then operate
normally when connected to XDP. Ensure that an annunciator is notconnected directlyto theXDPandBPatthesametime.

VARIOUS OPERATING MODES

ON-BOARD LINKS: In order to quickly and easily change operating modes for
different applications, the meter hasseveral "on-board links". They are designedtobe
easily opened(cut) or shorted (soldered). Do not connect more than one meter to the
same powersupply ifthe meterscannot use the same signal ground. Taking anyinput
beyond the powersupply railswill damage the meter.

V+

1

V+

31

+

±200mV

Links 1, 2,3&4SHORTED.

IN HI

30

IN LO

-

V-

26

Measuring a floating voltage
source of 200mV full scale.

V+

1

V+

31

IN HI

R

R=

30

0.2

FSR

I

Links 1, 2, 3, 4 SHORTED.

IN LO

V-

26

V-

Measuring current
Supply MUST be isolated.

+

±200mV

-

V-

Links 1,3&4SHORTED.

Measuring a single ended input
referenced to supply.

+

V1

-

+

V2

-

Measuring the ratio of two voltages.
Reading = 1000 V /V

50mV< V <200mV
V <2V .

2

12

31

30

30

36

35

31

V+

IN HI

IN LO

IN HI

IN LO

REF HI

REF LO

12

V-

V+

V-

1

26

1

26

V+

0V

V+

V-

Normally
SHORTED
Cut to
OPEN

IIN

220K

6R2

5K

IOUT

Links 1,3&4SHORTED.

1

V+

31

IN HI

30

IN LO

32

COM

V-

26

Measuring 4-20mA to read 0-999.
Supply must be isolated.

Normally
OPEN
Solder to
SHORT

V+

V-

Specifications liable to change without prior warning DPM 500S Issue 6 August/2002 M.C. Applies to DPM 500/7