PM-Series
3 1/2 DIGIT with 0.4 LED
General Features
The PM-35U Digital Panel Meter is an economical, high performance instrument incorporating a number of fea tures usually found only on more expensive meters. Utilizing the dual slope method of integration, the unit measures differential and single-ended DC voltages over five user selectable ranges from 199.9mV to 199.9V full scale.
Maximum res o lu tion is 100V over 1999 counts. Provision is made for user con nec tions to provide various operating modes, including a ra ti om et ric voltmeter, current meter, ratiometric ohmmeter, and a tem pera ture difference meter.
The true differential input capability of the Model PM-35U is particularly useful for making accurate measurements of very small signals in the presence of much larger common mode signals.
Because of its high noise immunity, it is also ideal for measuring various balanced transducers and bridge inputs. When measuring bridge circuits, long term drift of the excitation voltage can be compensated for by using the ratiometric voltmeter mode of operation.
SINGLE-ENDED METER200mV Range, >2V Range 200mV Range:
1) Change R6 from 470k to 47k, 5%; 2) Change R9 from 18.2k to 26.7k, 1%; 3) Remove R8 (9.53k) and short with a jumper; 4) It is recom mend ed that C4, C5 and C7 be changed to 0.22mF; 5) Adjust R10 until CV1=100mV.
>2V Range: Install R1 and R2 as specified under section titled Useful Tables.
View more application connections and connection instructions on page 3.
Specifications
Input Configuration:......True differential and single-ended
Full Scale Ranges:........199.9mVDC
1.999VDC (standard)
19.99VDC
199.9VDC
Input Impedance:...........Exceeds 1000M on 200mV and
2V ranges; 10M on all other ranges
Input Protection:............250VDC or 175VAC maximum on
200mV and 2V ranges; 1200VDC or 850VAC on all other ranges
Accuracy:.......................(0.1% of reading + 1 digit)
Temperature Coefficient:..5PPM/C in ratiometric operation; 80
to 100PPM/C using internal reference on 200mV and 2V ranges
Warm Up Time:..............2 minutes to specified accuracy
Conversion Rate:...........3 readings per second nominal
Display:...........................0.4" LED
Decimal Selection:........User programmable to 3 positions
Overrange Indication:...When input exceeds full scale on
any range being used, most significant 1 digit & polarity symbol are displayed with all other digits blank
Power Requirements:...+4.5 to +5.5VDC at 200mA max.
Operating Temperature:....0 to +60C
Storage Temperature:...-20 to +70C
Relative Humidity..........95% (non-condensing)
Case Dimensions:.........Bezel 2.76 x 1.17 (69.75 x 29.7mm)
Depth behind Bezel 3.32(84mm) plus 0.68 (17.27mm) for connector.
Weight:.............................88 gms (3.1 oz)
PM-35A.................... 3.5 digit Red LED, Precision Preference, 2VDC, 5VDC Power PM-35U.................... 3.5 digit Red LED, Low Cost, 2VDC, 5VDC Power
PM-45L................ 4.5 digit Red LED, Precision Meter w/Differential Input PM-45X............... 4.5 digit LCD, Precision Meter w/Differential Input PM-45XU.................3.5 digit LCD, Low Cost Meter w/Differential Input
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Connector Pinouts
The Texmate Model PM-35U inter con nects by means of a standard PC board edge connector having two rows of 10 pins, spaced on 0.156" centers. Connector are available from Texmate, or from almost any connector manu fac turer. Pro vi sion has also been made for direct solder termination to the PC board, thus elimi nat ing the need for a connector. Please note that the warranty will be void if there is any damage due to soldering.
Calibration Pot
Pins A, 1 and 3Decimal Select: Decimal points may be displayed as required by connecting appropriate pin to Decimal Select Common Pins B or 2.
Pins B and 2Decimal Select Common: Decimal points are displayed as required by connecting Pins B or 2 to the appropriate Decimal Select Pins A, 1, or 3.
Pin DReference Input: Reference voltage input for A to D convert er. Normally supplied from Reference Voltage Output Pin 4 which is internally jumpered to Pin D by way of Junction J1. Pin D may be used as an input for ratiometric measurements. Minimum usable voltage is.05VDC with +4.0VDC being the maximum.
Pin EAnalog Common: 2.8V output referenced to +5V System Power Input L, approximately +2.2V output referenced to Power Ground Input Pin K.
Pins F and 6Signal High Input: Signal high input of A to D converter. Maximum overvoltage protection is 250VDC or 175VAC.
Pins H and 7Voltage Divider Signal High Input: Signal high input for voltages that require attenuation or scaling. Dividing resistors R1 and R2 may be mounted internally for voltages up to 200V
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max. Matched dividing resistors for 2V (1/10) and 200V (1/100) ranges are available from Texmate. Shunt resistors for current measurements up to 200mA may be internally mounted in the R2 position. The current loop is then applied to Signal High Input Pin F and returned through Pin J or Pin 8.
Pins J and 8Signal Low Input: Signal low input of A to D convert er. Maximum overvoltage protection is 250VDC or 175VAC.
Pins K and 9Power Ground Input: Negative terminal of + 5VDC power should be connected to Pin 9. All digital signals, decimal points, display test, and overrange should be returned to this ground point.
Pins L and 10- +5VDC System Power Input: Meter requires regulated (10%) 5VDC power at approximately 200mA.
Pin 4Reference Voltage Output: Internal precision voltage ref er ence. Standard output is 1.000V, adjustable to 5% by R10 potentiometer. Usable voltages from.05V to 2.8V for special high impedance scaling can be obtained by changing the value of internal dividing resistors R8 and R9.
Pin 5Display Test: All segments will light up when Pin 5 is connected to +5VDC System Power Input Pin L or Pin 10.
COMPONENT SIDE
SOLDER SIDE
SPAN Potentiometer (Pot)
The SPAN pot is on the right side of the display. Typical adjustment is 20% of the input signal range.
Apply power to the meter. Then with a precision DC reference source, apply +1.900VDC be tween the Sig nal High Input Pin F and the Signal Low Input Pin J. Adjust R10 po ten ti om e ter (on left side as viewed from rear) until the display reads +1.9900V. Note: The voltage ap plied in this case is for a 1.999V F.S. meter. For other ranges, the voltage applied should be similarly pro por tion ate to the particular full scale voltage.
The PM-35U may be used in a wide variety of configurations.
The following circuits illustrate some of the possibilities and demonstrate the exceptional versatility of Texmate products.
Components called for in the applications which are not part of the standard meter may be supplied by the user or in some cases purchased from Texmate. The circuit diagrams explain the basic pinout connections required for each application.
Unless otherwise specified, the diagrams will show the component values and solder junctions that would normally be installed on a standard 2V range meter. For those applications which have alternative ranges and/or input configurations, the required component values and any modifications are
described in the text.
NOTE: Use of these application circuits is entirely at the risk and responsibility of the user and any user modification of the meter may at the discretion of Texmate, void the warranty. (See rear page for user's responsibility and warranty details) The following legend applies to all application circuits: 1) optional component positions are shown in dotted lines; 2) internal solder junctions are shown by for a closed junction or for an open junction; 3) calibration voltages as measured by an external user supplied voltmeter are shown by
R1 F.S. In
200mV omit
omit 2V
9M 20V
10M 200V
R2 Resolution
omit
omit
100k
100V
1mV
10mV
100mV
Rs External
0.01
0.1
Rs Internal
100
Resolution
10mA
1mA
Resolution
100A
10A
1A
100nA
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PANEL CUTOUT
FRONT VIEW
SIDE VIEW
TOP VIEW
When extra panel mounting tightness is required, optional Screw Mounting Clips can be purchased seperately and attach to the sliding mounting side clips
option metal
screw mounting clip
Standard Options for this Model Number
Special Options and Accessories
Part Number Description
4BASIC MODEL NUMBER
PM-35U..... 3.5 digit Red LED, Low Cost, 2VDC, 5VDC pwr
Note: For operation, the PM-35U requires a CN-L10 Dual Row 10 Pin PCB edge connector 0.156 center or equivalent (see accessories).
Part Number Description
4SPECIAL OPTIONS (Specify Inputs & Req. Reading) ZS..........Custom display scaling within standard ranges ZR-200V....200 VDC Range Change.
ZR-20V......20 VDC Range Change.
ZRS-200MV..200 mVDC range change.
ZRS-PMRP...Non-standard range and scale.
4ACCESSORIES
CN-L10...... Dual Row 10 Pin Connector, Solder Type
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Texmate is an American manufacturer of high durability industrial grade panel meters, bar graphs, and transducers. Texmate's meters are frequently equipped with relays and various signal outputs for industrial automation applications and are known for their extremely long service life.