SM-Series
0.48 LCD Display
The SM-35X is one of Texmate's new SM-series meter range.
This range, which includes meters with LCD and LED displays, offers many unique features designed to simplify installation, calibration and scaling. All SM-35 and SM-35X meters are pin-compatible, which enables LED and LCD meters to be interchanged within the same panel without necessitating wiring or panel cutout changes.
All SM-series meters are 5 V DC powered with bipolar single-ended inputs. The meters feature Display Hold, Display Test and Auto-Polarity indication. The polarity indication may be disabled or reversed by repositioning jumper clips on internal header pins. The SM-series of meters are designed to be user scalable to almost any engineering unit of readout. On-site scaling and recalibration is facilitated by multi-turn potentiometers that provide continuous fine and coarse adjustment within each of the three header-programmable full scale ranges.
The three ranges provided with the SM-35X (LCD display ) and the SM-35 (LED display) are 2 V, 20 V, and 200 V full scale and both of these meters can be ordered with an optional zero-offset adjustment potentiometer.
SM-35MV (LED display) is specially designed for low voltage inputs and provide three header-programmable input ranges of
20 mV, 200 mV, and 200 V full scale. SM-35MV has zero-offset adjustment potentiometers as a standard feature and a unique constant current power supply that eliminates any ground loop noise.
DC VOLTMETER
Input Configuration:... Single-ended, with optional provision
to offset the zero of the reading displayed
Input Impedance:........ 1M minimum
Full Scale Ranges:..... 2 V DC (Standard Range) 20 V DC
200 V DC (All ranges are header selectable)
A/D Converter:............ 12 Bit Dual Slope
Accuracy:.................... (0.05% of reading + 2 digits)
Temp Coefficient:....... 100ppm/C typical
Warmup Time:............ One minute to specified accuracy
Conversion Rate:........ 3 readings per second
Display:........................ 0.48" Liquid Crystal Display (LCD);
"Display Hold" & Dummy Zero
Decimal Selection:..... User programmable to 3 positions
Polarity:....................... Automatically displays both + or signs; header programmable polarity disable and reversal
Over-range Indication: When input exceeds full scale on
any range being used, the most significant 1 digit and + or symbol is displayed with all other active digits blanked
Power Supply:............ +4.5 to +5.5V DC at 5mA
Operating Temperature: 20 C to +60 C
Storage Temperature: -20 C to +70 C
Relative Humidity:...... 95% (non-condensing)
Case Dimensions:...... Bezel (2.755W x 1.170H)
69.68mmW x 29.72mmH Depth behind bezel (3.315) 84.2mm Plus (0.685) 17.4mm for connector
Weight:........................ 88 gms (3.1 oz)
143 gms (5 oz) when packed
SM-Series LED Displays SM-Series LCD Displays SM-35...............3.5 digit Red LED, 2 /20/200VDC, 5VDC Pwr SM-35MV........... 3.5 digit Red LED, 0.02/0.2/2VDC, 5VDC Pwr
SM-35X............. 3.5 digit LCD, 2 /20/200VDC, 5VDC Pwr
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Connector Pinouts
For most applications where it is not necessary to activate Display Hold, Display Test, or remotely change the selected decimal point and dummy zero, the three screw terminal blocks supplied with the meter can be used to connect Signal Low Span Fine
Input and Power Supply Ground (joined on the one terminal), Signal High Input and +5 V DC Power Input. For other applications, the Texmate SM-35X interconnects by means of a standard PC board edge connector having two rows of 10 pins each, spaced on 0.156" centers. Connectors are available from 6 4 Texmate, or from almost any connector manufacturer.
REAR OF METER WITH PCB EDGE CONNECTOR MOUNTED (For mounting of screw terminal blocks see below)
Pin A,C, 1 and 3 - Decimal Select and Dummy Zero: Decimal points and dummy zero may be blanked as required by carefully scraping off the fine tracks linking these pins to Decimal Select Common using a pair of pliers or a small screwdriver blade. Re-connect either by linking the appropriate pins on the connector or by solder-bridging the junctions located on the PC board edge fingers. CAUTION: Do not connect either the dummy zero or the decimal select to power supply ground.
Although the dummy zero and decimals will become activated when their select pins are grounded, this improper connection will eventually cause permanent damage to the display.
Pins B and 2 - Decimal Select Common: Common return pins for decimal point selection (see CAUTION above.) Pins J and K - Power Supply Ground: Power supply ground return (Note: Separate connections to Pins J and K and Pins 8
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and 9 are recommended when using edge connectors with the meter to minimize ground loop effects.) Pin L - Display Hold Input (CMOS compatible): If Pin L is left open, the meter will operate in a free-running mode. While Pin L is connected to +5 V DC Power Supply Input Pins 6 and 7, the meter will latch up; A/D conversions will continue but the display will not be updated until Pin L is released.
Pins 4 and 5 - Signal High Input: Signal inputs for all voltage ranges are applied to these pins. Maximum overvoltage protection is 400 V DC or 280 V AC. See CAUTION:ELECTRIC SHOCK HAZARD on rear page.
Pins 6 and 7 - +5 V DC System Power Input: The meter requires a regulated low-ripple 5 V DC power supply applied to these pins.
Pins 8 and 9 - Signal Low Input: Signal low input of the analog to digital converter circuits (Note: When measuring input signals (on the 2 V range) that are not isolated from the +5 V DC supply used to power the meter, a ground loop can be created that will cause the least significant digit to exhibit errors and instability. To avoid this problem the ground return path of the analog signal should be connected to the power supply ground only at the Signal Low Input Pins 8 and 9 of the meter.) Pin 10 - Display Test Input: All numeric display segments will operate when Pin 10 is connected to +5 V DC Power Supply Input Pins 6 and 7. CAUTION: The Display Test function is only intended for momentary operation. Continuous application of Display Test will, in time, damage the display.
Component Layout
Zero Offset
(optional)
ZERO Potentiometer (Pot) Optional
The Optional ZERO pot when installed is to the left of the SPAN pots (as viewed from the back of the meter). Typically it enables the displayed reading to be offset 1000 counts.
SPAN Fine Potentiometer (Pot)
The 15 turn SPAN Fine pot is on the left (as viewed from the back of the meter). Typical adjustment is 10% of the input signal range.
SPAN Coarse Potentiometer (Pot)
The 15 turn SPAN Coarse pot is on the right side (as viewed from the back of the meter).
Typical adjustment is 100% of the input signal range.
RANGE SELECT Header
Range values are marked on the PCB. Three positions are provided. After selecting a new range with the single jumper clip, recalibration is required.
Signal Conditioning Components (continued)
Polarity Display Header
This header allows the Polarity indication to be displayed normally, displayed reversed or to be disabled completely.
The meter is shipped from the factory with all the decimal points on. To turn off un wanted decimals, use a pair of long-nosed pliers to scrape off the fine tracks connecting decimals to decimal select common (alternatively, use a scalpel or small screwdriver). Re con nect by soldering where shown.
Calibration Procedure
CAUTION - ELECTRICAL SHOCK HAZARD See Below.
1) Select the F.S. input voltage range by re-positioning the jumper clip on the range select header as indicated by the voltages marked on the PCB.
2) Short Signal High Input Pins 4 & 5 to Signal Low Input Pins 8 & 9.
3) Adjust Zero Offset until the display reads zero.
4) Apply F.S. voltage.
5) Adjust Span Coarse & Span Fine controls; clockwise increases the displayed reading.
6) Adjust Zero Offset to offset the zero reading as required. (Re-calibration must be performed after changing ranges).
They provide the greatest convenience and ease of use
Texmates exclusive optional Push-On Connectors combine an edge card connector and a 10 position screw terminal block.
Push-On Connectors are ordered preconfigured for each specific power supply voltage and each optional power supply available for the SM-Series.
Part Number: CN-PUSH/SM
PCB Edge Connector
PCB Edge Connector
A standard 20-pin edge con nec tor (two rows of 10 pins on 0.156" centers) is used to connect the SM-35 meter. Order part no. CN-L10.
*Not Included
Texmates individual screw ter mi nal blocks offer a convenient al ter na tive to edge connectors for many ap pli ca tions, allowing com plete in stal la tion, con figu ra tion and calibration with out the need for soldering.
Slide each terminal block over the PCB until the hole aligns. Insert the re tain ing screw to secure.
Each kit includes: 3 plastic blocks with metal contacts, 4 screws with spade connectors, 1 metal contact and 3 quick disconnects.
Part Number: TB-KIT
AM-20........... 20 segment LED bargraph, 5V DC power
CM-35XTL...... Less than 1V DC loop drop and 1 Joule energy storage CM-35XT....... Economical 4-20mA loop-powered meter
PM-45X......... 4.5 digit 0.48 LCD DPM PM-45XU....... Lower cost version of PM-45X PM-45L......... 4.5 digit 0.4 LED DPM PM-45LU........ Lower cost version of PM-45L
SP-35X.......... Signal Power DC voltage measurement from 5.0V DC to 199.9V DC
PS-505....... 5V DC Regulated Power Supply, 0.5A Output PS-510....... 5V DC Regulated Power Supply, 1A Output
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PANEL CUTOUT
FRONT VIEW
SIDE VIEW
TOP VIEW
option metal
screw mounting clip
When extra panel mounting tightness is required, optional Screw Mounting Clips can be purchased seperately and attach to the sliding mounting side clips
Standard Options for this Model Number
Part Number
Description
Special Options and Accessories
Part Number
Description
SPECIAL OPTIONS (Specify Inputs & Req. Reading)
ZR......... Range Change from Standard Range shown in BOLD type V0-50K....... Zero offset potentiometer 50k...............
ZRS-SMUM.... Non-Std Range and/or Scale Changes for SM-35 series
ACCESSORIES
CN-L10....... Edge Connector with Solder eyelet, 10 Pin Dual CN-PUSH/SM.. Push-0n Screw Terminal Block Connector.....
TB-KIT.......... Terminal Block Connector Kit (3)...............
SL.CASERED.. Slim Bezel Case, Red Faceplate w/Mtg Hrdwre PS-505....... 5V DC Regulated Power Supply, 0.5A Output..
PS-510....... 5V DC Regulated Power Supply, 1A Output...
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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.