Martel Electronics DPM500 User Manual

DPM 500 3½ Digit LCD Module

The DPM 500 uses advanced components and construction techniques to provide a uniquely compact unit. The meter is in a 40 pin
DIL integrated circuit format that can be plugged directlyinto aDIL socket orpanel mountedusing the snap in bezel.For single rail use,
the DPM 500S-BL features a built in negative rail generator, enabling the meter to measure a signal referenced to its own power supply
0V.

12.5mm (0.5“) Digit Height

Programmable Decimal Points

°°

+

Auto-zero

-

Auto-polarity

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

Backlit Single Rail Version (DPM 500S-BL)

Annunciators

Standard Meter DPM 500

SCALING

Two resistors Ra andRb may befitted in orderto alterthe
full scale reading(F.S.R.) ofthemeter - 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
200mA 0R 1R

NOTE

Ensure link 10is cutif fitting Ra.

SAFETY

To complywiththe Low Voltage Directive (LVD93/68/EEC), input voltagestothe module’s pinsmust not exceed 60Vdc. Ifvoltages to the
measuring inputs doexceed60Vdc, then fitscaling resistors externallyto the module.The user mustensure that theincorporation 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).

Backlit Single Rail Version DPM 500S-BL

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 DPM 500 7.5 9 14
voltage DPM 500S-BL 3.5 5 6.5
Supply current DPM 500 150

(not inc. backlighting)

DPM 500S-BL 250
Backlight Voltage 5 V
(DPM 500S-BL) Current 30 60 mA
Input leakage current (Vin = 0V) 1 10 pA

* To ensure maximum accuracy, re-calibrate periodically.

CONNECTOR SOURCING GUIDE

METHOD 40 Pin DIL IC Socket

CF

µA

mV

kΩ

MHz

Stock Number

V

Aµ

DIMENSIONS All dimensions in mm (inches)

1.1

8.2

(0.04)

60.0 (2.36)

(0.32)

45.0 (1.77)

a. DPM 500 6.7 (0.26)

DPM 500S-BL 12.1 (0.48)

b. 4.80 (0.19)

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

30.0 (1.18)

16.0 (0.63)

Display in TEST mode

5.0

(0.19)

8.5 (0.33)

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

b

XG3

4.0 (0.16)

a

1

13

-

+

40

12

3

2

10

1

Rb Ra

12

7

5

4

7

REAR VIEW

9

11

20

8

15

14

DPM 500S-BL ONLY
ON-BOARD LINKS

OPTIONAL SCALING

21

RESISTORS

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.

Martel Electronics, Corp. P.O. Box 770 Londonderry, NH 03053
Toll Free: [phone] Phone: [phone] Fax: [phone]

PIN FUNCTIONS

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

15. - Input for the polarity annunciator. Internally linkedto POL(pin20). Ifthisis to be externally controlled, cut link 11.

16, 18, 19, 22 XB3, E3, AB, XG3. Outputs for use inauto-rangingapplications.

20. POL Drive for"-"annunciator. Internallyconnectedbylink11.

21. BP LCDbackplanedrive waveform.

23. DP3 1.999

24. DP2 19.99 See

25. DP1 199.9

26. V- Negative powersupply. Note that if the DPM 500S-BL is beingused, thevoltage betweenV+andV-must notexceed 6.5V.

27. XDP Connectto requiredannunciators/DPs (see note).

28. -5V Output fromnegative railgenerator circuit. This outputisaninversionofV+ (DPM 500S BL ONLY).

29. BG Input forbandgap reference.(1.22Vnom).

30. IN LO Negative measuring input. Analogue inputs must be no closer than 1Vto eitherthe positiveornegativesupply. The negative

31. IN HI Positivemeasuring input. supply of the DPM 500S-BL is generated internallyand mirrorsthepositivesupply voltage.

32. COM The ground for theanalogue sectionof theA/Dconverter, heldactively at2.8V(nom)belowV+. COMmust not be allowed to sink

33. REF- Negative output from internal reference.

34. REF+ Positiveoutput frominternalreference.

35. REF LO Negative input for reference voltage.

36. REF HI Positive input for reference voltage.

37. TEST Connecting this pin toV+ turnsonthesegmentsasillustrated. It should not be operated for more thana fewseconds asthe DC

40. V+/CLK Normally tiedto V+viaLink12but can be used to over ride the internaloscillator andcontrolthesampleratebycutting Link 12 and

SPECIAL NOTE: ANNUNCIATORS.

SPECIAL NOTE: ANNUNCIATORS.

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

µ

voltage applied to the LCD may "burn" thedisplay. This pin is nominally at 5V below V+and isthe groundfor thedigitalsection

of the meter, it can be usedas anegative supplytopowerexternallogicupto a maximum of 1mA.

making Link 13.

LED BACKLIT VERSIONS:

Apply 5V DC tothe backlighttabon the side of themeter. Typical currentis30mA. Forhigher voltages, fit a resistorin series.

E.g. For9Vuse150R. Maximum current =60mA.

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 mayappear when notwanted. To suppressunwanted annunciators, linkthem to
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 not connecteddirectly tothe XDPandBPatthesametime.

VARIOUS OPERATING MODES

ON-BOARD LINKS: In order to quickly and easily change operating modes for
different applications, the meter has several "on-board links". They are designed
to be easily opened(cut) or shorted (soldered).
Do not connect more than one meter to the same power supply if the meters cannot
use the same signal ground. Taking any input beyond the power supply rails will
damage the meter.

31

+

±200mV

30

-

Links 1, 2,3&4SHORTED.

Measuring a floating voltage

IN HI

IN LO

V+

V+

1

±200mV

V-

26

V-

+

-

0V

1V min

Links 1, 3 & 4 SHORTED.

30

31

IN HI

IN LO

V+

V-

1

26

Split supply operation (DPM 500).

source of 200mV full scale.

V+

1

V+

31

IN HI

R

30

0.2

R=

I

FSR

Links 1, 2, 3, 4 SHORTED.

IN LO

V-

26

V-

Measuring current
(supply MUST be isolated).

+

1

V

-

+

V2

-

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

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

2

12

31

30

36

35

IN HI

IN LO

REF HI

REF LO

12

V+

V-

1

26

V+

V-

V+

14V max
7V min

V-

Normally
SHORTED
Cut to
OPEN

31

+

±200mV

Links 1,3&4SHORTED.

IN HI

30

-

IN LO

Measuring a single ended input
referenced to supply (DPM 500S-BL).

IIN

31

IN HI

6R2

220K

5K

30

IN LO

32

COM

IOUT

Links 1,3&4SHORTED.

Measuring 4-20mA to read 0-999
(supply must be isolated).

V+

V-

V+

V-

1

26

1

26

Normally
OPEN
Solder to
SHORT

V+

0V

V+

V-

Specifications liable to change without prior warning DPM 500 Issue 4 July/1999 M.C. Applies to DPM 500/7