NANO www.murata-ps.com DMR20-1-TMP Digital Thermometer with Thermistor Probe FEATURES 40 to +105C (40 to +221F) measurement range Celsius or Fahrenheit readings Supplied with thermistor probe Installs in round oiltight 1.20 inch (30.5mm) cutouts Operates from 24Vac or 6 to 50Vdc supplies Reverse polarity protected to 75Vdc Four-digit LED display with C and F annunciators Over-temperature and open/shorted thermistor indication Two display brightness settings: 3mA (lo) 5mA (hi) Murata Power Solutions new DMR20-1-TMP thermistor-input thermometer modules Screw-style terminal blocks simplify installation provide a simple cost-effective way to accurately measure air temperatures from -40 to Self-resetting internal fuse for long term reliability +221F (-40 to +105C). The user can choose between Celsius or Fahrenheit readings via Front panel moisture resistance to IP67/NEMA 6 a rear pc-board jumper. Each thermometer is supplied with an epoxy-dipped NTC thermis- Supplied with EPDM rubber gasket and plastic hex nut tor probe and is factory-calibrated to a typical accuracy of 1F. The probe features 18 inch (46cm) long leads to allow for remote installation. Panel knockout punches and tooling available Operating power can be from either 24Vac (50/60Hz) or 6 to 50V DC supplies. Two display-brightness levels are provided to ensure optimal readability under various ambient Performance/Functional Speci cations lighting environments. Typical power consumption from a 12 or 24Vdc supply is 3mA in the Typical at Ta = +25C, V = 1224Vdc or 24Vac (5060Hz), supply unless otherwise noted low brightness setting, and 5mA in the high-brightness setting. A built-in resettable fuse Power Supply (TB1) assures long term reliability, and all units are reverse polarity protected to -75Vdc. DC Input +6 to +50Vdc Their large, 0.30 in./7.6mm, bright LED displays can be easily read from 10 feet away (3 AC Input 24Vac (47-63Hz), 15% Reverse Polarity Protection -75Vdc (min.) meters). Visual indications alert the user to over / under temperature conditions, as well Low brightness: 4.5mA (max.) as an open or shorted thermistor. DMR20-1-TMP thermometers employ a precision 0.2% Current Consumption High brightness: 6mA (max.) voltage reference and metal- lm resistors to achieve outstanding performance over an NTC Thermistor (TB2) operating ambient temperature range of 25 to +60C. Resistance at +25C 10k, 3% (max.) The DMR20-1-TMP features a round polycarbonate housing that provides excellent protec- B 3988K, 0.5% 25/100 Time Constant 20 seconds (typ.) tion against moisture, dust, shock and vibration. The supplied hardware is designed to Operating Temperature -40 to +105C provide moisture ingress protection to IP67/NEMA 6. Panel installation is straightforward: Insulation Resistance (100V) 100 M (min.) using available tooling, punch a 1.2 inch (30.5mm) diameter hole, insert the thermometer Performance and gasket into the panel, and securely fasten using the supplied plastic hex nut. Sampling Rate 1 reading/second Resolution 1 degree Fahrenheit or Celsius Accuracy at +72.0F (+22.2C) 1 (typical), 2 (max.) Celsius Measurement Range -35 to +105C Operation and accuracy at supply voltages above or below this range are not speci ed. DMR20-1-TMP series thermometers are supplied with a 10k Ohm NTC thermistor probe that has a maximum operating Fahrenheit Measurement Range -31 to +221F temperature of +221F (+105C). The thermistor must not be immersed in uids of any kind, including water. Overrange Indication See footnote The accuracy and measurement range speci cations cited are achieved with the factory-supplied 10k Ohm NTC thermistor Temperature Drift (from -25 to probe. 0.03 counts/C (typ.) +60C) Measurements at temperatures in the range of -32F to -40F (-36C to -40C) will decrease the accuracy to 3 max. Mechanical Measurements at temperatures in the range of +221F to +230F (+105C to +110C) will decrease the accuracy to 3 max. 1.5 in. diameter x 1.0 depth in. Dimensions Overrange condition: measurements from -41F (-41C) to -50F (-46C) will cause the display intensity to ash from (38.1 x 25.4mm) bright to dim to indicate a low temperature overrange condition where accuracy is no longer valid nor speci ed. Measure- Display Type Four digit, LED, 0.30 in. (7.6mm) ments from +221F (+105C) to +230F (+110C) will also cause the display intensity to ash from bright to dim to 0.74 ounces (21 grams) with nut, indicate a high temperature overrange condition, but accuracy is still valid to 3 max. Weight gasket, and thermistor probe An open or shorted thermistor condition at terminal block TB2 will be displayed as F or C. Measurements Housing Material Polycarbonate below -50F (-46C) or above +230F (+110C) will also be displayed as an open or shorted thermistor. -25 to +60C is the operating temperature range of the DMR20-1-TMP module, and not the measurement range of the Terminal Block Torque (TB1 & TB2) 2.2 in-lbs (0.25 N-m) 20% supplied NTC thermistor probe. 2 2 18-26AWG (1mm to 0.14mm ) Wire size and Type copper, solid or stranded Wire Insulation Strip Length 0.20 in. (5.1mm) Environmental Operating Temperature 25 to +60C Storage Temperature 40 to +75C Humidity (non-condensing) 0 to 85% (thermometer and probe) For full details go to www.murata-ps.com/rohs www.MeterCenter.com - www.DatelMeters.com - www.BikeMeters.com MPM DMR20-1-TMP.A01.D2 Page 1 of 4NANO DMR20-1-TMP Digital Thermometer with Thermistor Probe Ordering Information DMR20-1-TMP-R-C Digital Thermometer (Red LED) with NTC Thermistor JP1 IN: HI BRIGHTNESS JP1 OUT: LO BRIGHTNESS Tooling JP1 DMR20-1-KP 1.2 in. (30.5mm) Round knockout punch (no keying notch) JP2 JP2 IN: FAHRENHEIT CAL R3 1.2 in. 930.5mm) Round knockout punch (with four keying F1 DMR20-2-KP JP2 OUT: CELSIUS notches) DMR20-3-KP 1/8 in. and 3/16 in. (3.2 and 4.7mm) key-notch nibbler tool TB1 TB2 Note: An M30 x 1.5 nylon hex nut and EPDM sealing gasket are supplied with each ther- mometer. The -C suf x denotes RoHS compliance. Figure 1. Jumper con guration TECHNICAL NOTES IMPORTANT To ensure safe and reliable operation, DMR20-1-TMP 4. Panel Installation: Other than the factory-supply thermistor probe thermometers must be installed and serviced by quali ed techni- connected to TB2, all electrical connections to DMR20-1-TMP must cal personnel. Contact Murata Power Solutions if there is any be made after the unit is securely attached to the panel, and with its doubt regarding installation or operation. DC supply input de-energized (off). In high-vibration environments, adequate strain reliefs must be used on all wiring connected to TB1 1. Operating Input Range: As shipped, the DMR20-1-TMP is con gured and TB2. See Figure 2 for typical panel mounting details. for degrees Fahrenheit readings with jumper JP2 closed as indicated by the LED displays F annunciator. Removing JP2 from its 2-position Tightening Torque: header (i.e., opening it) places the unit in the degrees Celsius reading The recommended tightening torque for the M30 x 1.5 plastic hex nut mode and turns on the C annunciator. is 10 to 17 in-lbs (1.3 to 1.9 N-m). If a torque wrench is not available, this recommended range can be approximated by hand tightening the Jumper JP1 selects either the display low brightness mode (JP1 out or hex nut clockwise until it just bottoms out against the panels rear sur- open), or the high brightness mode (JP1 in or closed). face. From this bottomed-out reference position, using a suitable tool, Con guration changes to jumpers JP1 and JP2 should only be made tightening the hex nut turn clockwise will produce approximately 10 when the unit is off (de-energized). in-lbs (1.3 N-m) of torque tightening it 3/8 turn clockwise will produce 2. Thermistor Probe Considerations: Terminal block TB2 is internally approximately 17 in-lbs (1.9 N-m). connected to a high-impedance ampli er which, in some operating Check to make sure the housings anti-rotation key is aligned with the environments, may be susceptible to noise that produces unsteady or notches on both the panel and the gasket before tightening the hex erratic temperature readings. Please note, the thermistor probe and nut. Over tightening the hex nut will distort the rubber gasket and may its wire leads are not electrically isolated from the power source con- damage the threads on both the nut and the housing, thereby compro- nected to TB1. mising the installations mechanical integrity and its ability to protect Operation in humid environments is permissible up to a relative humid- against environmental effects. ity of 85% as long as condensation does not form on the thermistor Panel Thickness: probe body or the thermometer itself. The supplied thermistor probe When using both the factory supplied EPDM gasket and hex nut (the must never come in direct contact with any liquids, solvents, or cor- recommended standard installation method), the DMR20-1-TMP can be rosive substances. mounted in panels ranging from 0.032 in. to 0.250 in. (0.8 to 6.4mm) 3. Calibration: DMR20-1-TMP thermometers are calibrated with the thick. When the gasket is not used, the panel thickness range is 0.075 factory-supplied NTC thermistor probe connected to TB2. Under in. to 0.325 in. (1.9 to 8.3mm). However, using the factory supplied normal operating conditions, periodic recalibration is not required. The hardware and tightening torque recommendations results in optimal supplied thermistor probes 3% tolerance is nulled by adjusting the resistance to vibration, and dust and moisture ingress. rear-mounted CAL potentiometer R3. Recalibration must always be Panel Materials: performed if the supplied thermistor is replaced with another 10k Ohm Acceptable panel materials include aluminum, mild steels, plastics, NTC thermistor that meets the B = 3988K (0.5%) speci cation. 25/100 FR-4 pc-board, and many other materials with a at matte surface on Operation and performance with thermistors that do not fully meet the both sides of the cutout. The DMR-20-x-KP tools can be used with most thermal characteristics of the factory supplied probe are not speci ed. panel materials, except for stainless steel or other hardened metals. To achieve the best overall accuracy, calibration should be performed DMR20-1-TMP has passed vibration testing combined with tempera- with the unit con gured for Fahrenheit reading (JP2 closed), with the ture cycling while mounted to the materials noted above, using the probe at an ambient temperature of 72F, 6 (22C, 4), adjusting speci ed tightening torques. If the unit will be mounted to extremely R3 to match the readings of a user-supplied thermometer with known smooth or slippery surfaces, the user is advised to test the completed accuracy and a resolution of 0.1F as a reference. MPM DMR20-1-TMP.A01.D2 Page 2 of 4