®
®
DMS-40PC-4/20S
4-20mA Input
4½ Digit Process Monitors
with Full-Size LED Displays
Order on-line at www.datel.com
Features
•
Full-size, 0.52" (13.2mm) high, LED digits
•
+7.5- 32Vdc model draws 30mA
•
+24V Isolated-power models
•
Dip-switch selectable range, offset, and
decimal points
•
Non-interacting, 20-turn, gain (span) and
offset (zero) adjustments
•
Insensitive to ground loops
•
103 Ohm max. loop burden
•
Vibration-resistant package; reliable screw-
terminal connections
•
Hundreds of different input/readout
combinations
•
Miniature size: 2.17" x 0.92" x 1.02"
(55mm x 23mm x 26mm)
New +24V Isolated-Power Models
The DMS-40PC-4/20S Series' superior design makes them ideal for use in
demanding 4-20mA process monitoring applications requiring a full 4½ digits (0-19999)
of display resolution. Their full-size, 0.52" (13.2mm) high, LED displays can be read in
virtually any lighting condition and are available in green, high-intensity red, or low-
power red.
Two operating power supply ranges are available: a wide-input +7.5 to 32V model
for use with popular +12Vdc and +24Vdc industrial supplies, and +4.75 to 5.25V
models for use with +5V logic supplies. The reverse-polarity protected +7.5-32V red
LED model consumes only 30mA from a +24V supply, but still provides excellent
display brightness.
The DMS-40PC-4/20's input, span, and offset circuits all employ super-stable,
±0.5% thin-film chip resistors. Long-term stability and accuracy are assured by driving
these tight-tolerance resistors with an ultra-stable, ±0.2% bandgap voltage reference.
And, unlike many competing designs, the two precision 20-turn span and zero adjust
potentiometers do not interact with one another.
All range-change and decimal point selections are made by configuring two gold-
plated, vibration-resistant, six-position DIP switches. To further enhance reliability, both
power supply and current loop connections are made via reliable screw-type terminal
blocks. All these outstanding features make the DMS-40PC-4/20S Series meters the
most rugged 4½ digit LED display process monitors available.
4½ DIGIT A/D
CONVERTER
Range
Offset
Gain
DATA
R3
ZERO
ADJUST
R7
GAIN
ADJUST
DP1
DP2
DP3
DP4
BAND-GAP
REFERENCE
CIRCUIT
ON
S1
1
2
3
4
5
6
S2
1
2
3
4
5
6
ON
+5V
VOLTAGE
CONVERTER
SG9
+5V
CURRENT TO
VOLTAGE
CONVERTER
TB1
1
2
TB2
1
2
1
+
–
+
+V
–
–V
-V is not connected to meter
ground on ‘-I’ suffix models.
4-20mA
CURRENT LOOP POWER
POWER
SUPPLY INPUT
Figure 1. DMS-40PC-4/ 20S Simplified Schematic
DATEL, Inc., Mansfield, MA 02048 (USA)
•
Tel: (508)339-3000, (800)233-2765 Fax: (508)339-6356
•
E-mail: sales@datel.com
•
Internet: www.datel.com
DMS-40PC-4/20S
4½ DIGIT, 4-20mA INPUT, LED DISPLAY METERS
Performance/Functional Specifications
Typical at T
A
= +25°C, unless otherwise noted.
Current Loop Input
Full Scale Input Range
(1)
Loop Impedance
(2)
Voltage Drop
(2)
Overcurrent Protection
Performance
Sampling Rate
Adjustable Accuracy
(15 min. warm-up)
Temperature Drift of Span
(3)
Temperature Drift of Zero
(3)
Power Supply Requirements (4)
DMS-40PC-4/20S-5RS
DMS-40PC-4/20S-5GS
DMS-40PC-4/20S-5RH
DMS-40PC-4/20S-5RL
DMS-40PC-4/20S-24RL
DMS-40PC-4/20S-24XX-
I
Models
Display
Display Type and Size
Polarity Indication
Overrange Indication
Physical/Environmental
Operating Temperature
Storage Temperature
Humidity (Non-condensing)
Case Material
Weight
0
–40
0
—
—
—
+50
+75
95
°C
°C
%
4½ digit LED, 0.52"/13.2mm high
"-" for negative readings
Flashing "0000"
+4.75 to +5.25Vdc at 140mA max.
+4.75 to +5.25Vdc at 140mA max.
+4.75 to +5.25Vdc at 140mA max.
+4.75 to +5.25Vdc at 50mA max.
+7.5 to +32Vdc at 50mA max.
+21.6 to +26.4Vdc at 60mA max.
—
—
2.5 readings per second
To ±0.01% of full scale ±2 counts
±0.3
±0.2
±0.6
±0.5
Cnts/°C
Cnts/°C
Min.
+3.7
12
—
—
Typ.
—
—
—
—
Max.
+20.4
103
2.1
±40
Units
mA
Ohms
Volts
mA
Technical Notes
(1) Full Scale Input:
The DIP Switch settings display readings in Table 1
can typically be obtained with transmitters having a low-level output of
3.7 to 4.3mA and a full-scale output of 19.4 to 20.4mA. When using
transmitters whose outputs fall outside these ranges, try using the
next highest DIP switch setting if the desired reading is too low, or the
next lowest setting if the desired display reading is too high. Example
number 2 illustrates this point.
Please keep in mind that the DMS-40PC meter from which the DMS-
40PC-4/20S is derived has an accuracy specification of ±3 counts
(max.); thus, it may not always be possible to obtain the exact desired
display readings. A change of ±1 count is defined as the right-hand
most digit (the"ones" LED) going up or down by one.
Other display readings not shown in Table 1 are obtainable. For
example, some negative readings with a 4mA input are possible.
Consult DATEL for more information regarding display readings not
shown in the table.
(2) Loop Impedance/Drop:
The maximum loop impedance and the
maximum loop voltage-drop are both specified with DIP switch setting
#20 enabled. The maximum loop voltage drop is specified with a
20.0mA input current.
(3) Temperature Drift:
Temperature drift of zero and temperature drift of
gain are both specified with the meter configured for range #20 with
4mA adjusted (using R3) to read "0000" ±1 count, and 20mA adjusted
(using R7) to read "19000" ±2 counts.
The temperature drift of gain is proportional to the full scale range
being used. It is typically less pronounced at the lower range settings,
that is, if the observed gain drift of a particular meter is +12 counts
when reading "19000" on range #20 at 40°C, the same meter will
most likely have a drift of only +6 counts when reading "9000" on
range #12 at 40°C.
The normally very accurate autozeroing feature of the DMS-40PC-4/
20S's internal analog-to-digital converter (A/D) is not a factor in
determining the meter's zero-reading stability over temperature due to
the fact that an offset voltage is applied to the A/D's LO input. This
offset voltage is used to null the voltage developed with a 4ma input.
To function properly, the autozeroing feature found in most digital
panel meters requires both A/D inputs to remain at zero volts with
varying temperature. The meter's zero-reading stability over its
specified operating temperature is affected by the drift of three terms:
the voltage developed by the meter's offset circuitry; the voltage
developed across the meter's input resistor(s) with a 4mA input; and
the stability of the applied 4mA input signal itself. In the lower DIP
switch settings ( ranges #1-4), the meter's parasitic etch and switch
interconnect resistances also contribute a small error.
The meter's performance with regards to span stability over tempera-
ture is affected by the drift of the meter's gain circuitry and the drift of
the input resistor(s). To counter these drifts in applications requiring
the utmost in temperature stability, where possible, the meter should
be calibrated at its anticipated operating temperature. For these
applications, use of the DMS-40PC-4/20S-5RL model is highly
recommended because of its inherently lower power consumption and
self-heating.
Polycarbonate
1 ounce (28grams)
Order on-line at www.datel.com
Ordering Information
+5V supply, standard-intensity red LED's
+5V supply, standard-intensity green LED's
+5V supply, low-power red LED's
+5V supply, high-intensity red LED's
+7.5V to +32V supply, low-power red LED's
+24V isolated supply, standard-intensity
red LED’s
DMS-40PC-4/20S-24RH-
I
+24V isolated supply, high-intensity red LED’s
DMS-40PC-4/20S-24GS-
I
+24V isolated supply, standard-intensity
green LED’s
DMS-BZL1
Panel-mount bezel assembly
DMS-BZL2
Panel-mount bezel assembly with
sealing gasket
DMS-30-CP
Panel cutout punch
A panel-mount retaining clip is supplied with each model.
DMS-40PC-4/20S-5RS
DMS-40PC-4/20S-5GS
DMS-40PC-4/20S-5RL
DMS-40PC-4/20S-5RH
DMS-40PC-4/20S-24RL
DMS-40PC-4/20S-24RS-
I
DATEL, Inc., Mansfield, MA 02048 (USA)
•
Tel: (508)339-3000, (800)233-2765 Fax: (508)339-6356
•
E-mail: sales@datel.com
•
Internet: www.datel.com
2
4½ DIGIT, 4-20mA INPUT, LED DISPLAY METERS
DMS-40PC-4/20S
Table 1. DIP-Switch Settings
Switch S1
Display Reading
4mA
1.
0000
2.
0000
3.
0000
4.
0000
5.
0000
6.
0000
7.
0000
8.
0000
9.
0000
10.
0000
11.
0000
12.
0000
13.
0000
20mA
2250-2500
2500-2800
2800-3200
3200-3850
3850-4300
4300-4900
4900-5600
5600-6200
6200-6800
6800-7750
7750-8600
8600-9850
9850-11000
Off
Off
Off
Off
On
On
On
On
Off
Off
On
On
On
On
On
On
On
On
Off
Off
On
On
On
On
Off
Off
Off
Off
Off
Off
On
On
On
On
Off
Off
Off
Off
Off
Off
On
On
On
On
On
On
On
On
On
On
Off
Off
On
On
Off
Off
On
On
On
On
On
On
On
On
On
On
On
On
On
On
On
On
Off
Off
On
On
Off
Off
Off
Off
Off
Off
Off
Off
Off
Off
Off
Off
On
On
On
On
Off
Off
Off
Off
On
On
On
On
Off
Off
Off
Off
Off
Off
Off
Off
Off
Off
Off
Off
On
On
On
On
On
On
On
On
On
Off
On
Off
On
Off
On
Off
On
Off
On
Off
On
Off
On
Off
On
Off
On
Off
On
On
Off
Off
On
On
Off
Off
On
On
On
On
On
On
On
On
On
On
On
On
SW1
SW2
SW3
SW4
SW5
SW6
Switch S2
SW1
SW2
14.
0000 11000-12000
15.
0000 12000-13000
16.
0000 13000-14000
17.
0000 14000-15300
18.
0000 15300-16300
19.
0000 16300-17800
20.
0000 17800-20000
Since the DMS-40PC-4/20S uses extremely-stable thin-film chip
resistors, periodic re-calibration is typically required only in environ-
mentally demanding applications where shock, vibration and tempera-
ture extremes may have a detrimental affect on the 20-turn potentiom-
eters.
(4) Input Grounding:
Except for the “-I” suffix models which feature
isolated current loop inputs, all other DMS-40PC-4/20S meters are
supplied with their 4-20mA negative-input terminals (TB1-2, “-”)
internally connected to their power supply ground terminal (TB2-2,
“-V”). This single-ended input configuration is compatible with most
grounded-referenced 4-20mA transmitters.
Applications in which the DMS-40PC-4/20S and its associated 4-20mA
transmitter are connected to a common ground and the transmitter
drives two or more loads (for example, the meter is in series with a
PLC) must have the meter connected as the
first
device in the current
loop, that is, closest to the system ground (see Figure 2). If this
connection scheme is not possible and/or the meter must be connected
in the middle of the current loop, then‘-I’ suffix models
must be used
to
provide the required isolation between the meter’s current loop input
and the power supply ground (“-V”). See Figures 2, 3, 4, and 5 for
typical loop connections.
Using the Decimal Point Settings Table as a guide, the DMS-40PC-4/
20S's decimal points can be enabled to suit the user's particular readout
requirements. Place the selected decimal point's DIP switch to the ON
position (up) to illuminate the decimal point. The decimal points are
merely placeholders, that is, they can all be illuminated or all turned off;
they have no affect on the meter's operation and/or display readings.
Operating and Setup Instructions
The following procedure must be performed as the first re-calibration step
every time DIP switches S1 and S2 are changed to select a new display
range. The following procedure also assumes the DMS-40PC-4/20S is
initially completely mis-adjusted, i.e., both potentiometers and both DIP
switches S1 and S2 are randomly set. When performing switch settings,
make sure that the DIP switch's small actuator is pushed up as far as it
will go to ensure that the switch is truly set to the ON (closed) position.
1.
Set R7 (gain/span adjust) and R3 (zero/offset adjust) fully
clockwise, roughly 20 turns, then using the settings found in the
selected range, place the DIP switches on S1 and S2 to the
appropriate positions for the desired display reading.
2.
Apply a precision 4mA input with proper polarity and adjust R3
(top 20-turn potentiometer) until the meter's display reads "0000".
3.
Apply a precision 20mA input and adjust R7 (bottom 20-turn
potentiometer) until the display reads the maximum desired reading.
Repeat steps 2 and 3 to make sure the adjustments did not affect
one another.
Table 2. Decimal Point Settings
Switch S2
SW3
DP1
SW4
DP2
SW5
DP3
SW6
DP4
DATEL, Inc., Mansfield, MA 02048 (USA)
•
Tel: (508)339-3000, (800)233-2765 Fax: (508)339-6356
•
E-mail: sales@datel.com
•
Internet: www.datel.com
3
DMS-40PC-4/20S
4½ DIGIT, 4-20mA INPUT, LED DISPLAY METERS
4.
If necessary, select the appropriate decimal point by setting either
SW3, SW4, SW5, or SW6 of S2 to ON (DP1, DP2, DP3, or DP4,
respectively, as shown in Table 2).
NOTE:
Please keep in mind that the transmitter's 4mA and 20mA output
accuracy may affect display readings which are at, or very close to, the
high and low extremes of the selected range. See Example #2 below and
Technical Note 1 for more information.
Use DIP-switch setting #11. Apply 4mA and adjust R3 so the display reads
"0000". Apply 20mA and adjust R7 so the display reads "8600". If the
transmitter's full-scale output is less than 20.0mA, it may not be possible
to adjust R7 for a reading of "8600" with setting #11. If this occurs, select
setting #12 and re-calibrate both R3 and R7 to obtain "0000" and "8600".
Note that for these display readings no decimal points are used. Set SW3,
SW4, SW5 and SW6 on switch S2 to OFF.
S1
S2
3.
Desired display readings are:
4mA = "0000"
20mA = "10000"
1
2
3
ON
ON
Examples
The examples below illustrate how to configure the meter to perform some
typical measurements. Remember to first set R3 and R7 to their full
clockwise position before calibrating the meter.
S1
S2
1.
Desired display readings are:
4mA = "0.000"
20mA = "3.000"
1
2
3
ON
4
5
6
1
2
Use DIP-switch setting #13. Apply 4mA and adjust R3 so the display
reads "0000". Apply 20mA and adjust R7 so the display reads "10000".
For these display readings no decimal points are used. Set SW3, SW4,
SW5 and SW6 on switch S2 to OFF.
4.
Desired display readings are:
4mA = ".0000"
12mA = ".2500"
1
2
3
4
5
6
1
2
S1
ON
ON
S2
Use DIP-switch setting #3 and enable decimal point DP2 by placing SW4
of switch S2 to ON. Apply 4mA and adjust R3 so the display reads "0.000".
Apply 20mA and adjust R7 so the display reads "3.000".
2.
Desired display readings are:
4mA = "0000"
20mA = "8600"
1
2
3
4
5
6
1
2
S1
ON
ON
S2
4
5
6
1
2
This example is not as straightforward as the previous three. Notice that
12mA is exactly halfway between 4mA and 20mA. If we assume the input
could go up to 20mA, the display reading would then be 2 x .2500 or
".5000". From the table, we can select DIP-switch setting #7 and enable
DP1 via SW3 of switch S2. Apply 4mA and adjust R3 so the display reads
".0000". Apply 12mA and adjust R7 so the display reads ".2500".
CONNECTION DIAGRAMS
+24V
+
+
4-20mA
SINGLE-ENDED
TRANSMITTER
(TB1-1)
+V (TB2-1)
+
DMS-40PC-4/20S-24RL
–
24V GROUND
(TB1-2)
–
–V (TB2-2)
Figure 2. Typical Connections for Single-Ended Transmitters Driving
Single-Ended +24V Powered Meters.
DATEL, Inc., Mansfield, MA 02048 (USA)
•
Tel: (508)339-3000, (800)233-2765 Fax: (508)339-6356
•
E-mail: sales@datel.com
•
Internet: www.datel.com
4
4½ DIGIT, 4-20mA INPUT, LED DISPLAY METERS
DMS-40PC-4/20S
+24V
+
(TB1-1)
LOOP-POWERED
TRANSMITTER
+V (TB2-1)
+
DMS-40PC-4/20S-24RL
–
4-20mA
N.C.
(TB1-2)
–
–V (TB2-2)
24V GROUND
Figure 3. Typical Connections for Loop-Powered Transmitters
Driving Single-Ended Meters.
+24V
+V (TB2-1)
DMS-40PC-4/20S-24RL-I
(TB2-2)
–V
+
+
SINGLE-ENDED
TRANSMITTER
+
(TB1-1)
4-20mA
(TB1-2)
–
+
PLC or OTHER
SINGLE-ENDED
DEVICE
4-20mA
–
24V GROUND
–
Figure 4. Typical Connections for Isolated-Supply Meters in
Series with an Auxiliary Device.
+24V
+5V
+
+
4-20mA
LOOP
TRANSMITTER
(TB1-1)
+V (TB2-1)
+
DMS-40PC-4/20S-24RL
–
24V GROUND
(TB1-2)
–
–V (TB2-2)
5V GROUND
Figure 5. Typical Connections for +5V Powered Meters. Note that 5V Ground
and 24V Ground are Tied Together Inside the Meter.
DATEL, Inc., Mansfield, MA 02048 (USA)
•
Tel: (508)339-3000, (800)233-2765 Fax: (508)339-6356
•
E-mail: sales@datel.com
•
Internet: www.datel.com
5