Thermistors

Thermistors exhibit a precise and predictable change in electrical resistance when exposed to a corresponding change in temperature. Positive temperature coefficient (PTC) thermistors exhibit an increase in electrical resistance when exposed to an increase in temperature and Negative temperature coefficient (NTC) thermistors exhibit a decrease in electrical resistance when exposed to an increase in temperature. 

ACI Hazardous Thermistor Series features a ½ inch stainless steel probe with two, 22 AWG Etched Teflon colored lead wires to differentiate between the NTC sensor types. The sensors are manufactured using a double encapsulation process to eliminate moisture and the thermally conductive epoxy helps to increase response times. The heavy duty Feraloy Iron or Aluminum Connection Head comes standard. The sensors can be used in Duct, Wall Mounted and Immersion style configurations.

ACI Thermistor Duct Series is designed to be used in smaller duct applications and includes an insulation pad for sealing the duct and dampening vibration. The stainless steel probe features two, 22 AWG Etched Teflon colored lead wires to differentiate between the sensor types. The sensors are manufactured using a double encapsulation process to eliminate moisture and the thermally conductive epoxy helps to increase response times.

ACI Thermistor Flexible Averaging Series features an 18 AWG Plenum Rated cable sensing element with two, 12 inch 22 AWG Etched Teflon colored lead wires. The sensors are multipoint and provide a better overall average temperature on the air inside larger ducts when compared to a single point sensor.

Products

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$238.70
The ACI Thermistor Copper Averaging Series features a copper sensing element with AWG Etched Teflon colored lead wires to differentiate the different sensor types. Each sensor is manufactured with 4 or 9 sensing points determined by the length of the sensing element. The averaging sensors provide a better average temperature of the air inside the duct when compared to a single point duct sensor. Each of the elements is sealed to prevent moisture intrusion and includes a foam pad to seal the duct and dampen vibrations. The benefits of using a copper sensing element is that it has improved thermal conductivity and higher corrosion resistance than similar aluminum style averaging sensors. Additionally, copper has been proven to have an antibacterial effect to many of the airborne contaminants, mold and bacteria found in duct systems. Our standard enclosures include the galvanized “-GD” or plastic duct enclosure with hinged cover “-PB”. Each unit includes nylon wire ties and mounts with optional copper capillary and universal plastic mounting clips, NEMA/IP Rated Weather Proof enclosures and NIST certificates as referenced on the back of the product data sheet. Applications: Air Handlers, Roof Top Units, Mixed Air/Discharge/Supply Air Temperature Monitoring, Data Centers, Hospitals
$108.90
The ACI Thermistor Flexible Averaging Series features an 18 AWG Plenum Rated cable sensing element with two, 12” 22 AWG Etched Teflon colored lead wires to differentiate the sensor types. The sensors in this series are multi-point. Averaging sensors provide a better overall average temperature of the actual air inside larger ducts when compared to that of a single point sensor. All flexible averaging sensors are limited to being used in applications where operating temperatures are limited and high humidity, chemical resistance, and UV light sources aren’t required. Each of the sensing elements is protected using a dual wall adhesive lined heat shrink tubing to provide a basic level of moisture protection. The sensor length should be determined by the size of your duct. Standard enclosure options include a galvanized junction box “-GD” or plastic duct enclosure with hinged cover “-PB”. Each unit includes nylon wire ties and mounts for mounting. Optional copper capillary or universal plastic mounting clips, NEMA/IP Weather proof enclosures and NIST Certificates are available as referenced in the ordering grid on the back of the product data sheet. Applications: Air Handlers, Roof Top Units, Mixed Air/Discharge/Supply Air Temperature Monitoring, Data Centers, Hospitals
$323.40
The ACI Relative Humidity with Thermistor Outside Air Series utilizes a thermoset polymer capacitive sensing element with factory applied hygroscopic filter to deliver a proportional analog current or voltage output signal. The hygroscopic filter provides added resistance to moisture, dust, and other chemicals for greater long term reliability. The RH Outside Air transmitter features integral DIP switches for field selection of the proper output signal and supply voltage to meet your applications requirements. Each unit also contains 0%, 50%, and 100% test options to verify that the transmitter is both working and wired properly. Field calibration also can be performed by using the increment and decrement calibration DIP switches without the need to replace the sensing element. These enhancements provide increased flexibility and outstanding long-term reliability. Outside Air configurations feature a weatherproof Euro style enclosure with gasketed cover and conformally coated circuit boards for added moisture and chemical resistance. Three and Five-point NIST Calibration Certificates are available upon request but they must be ordered separately. Applications: Monitor Outdoor Air Humidity, Economizer Control, Psychrometric calculations such as Enthalpy and Dew point, Wash down Applications
$95.70
The ACI Thermistor Duct Series features a stainless steel probe with two, 22 AWG Etched Teflon colored lead wires to differentiate the different sensor types. The sensors in this series are manufactured using ACI’s proved double encapsulation process to eliminate the effects of moisture on the sensors and increased response times from our high quality, thermally conductive epoxy. The duct sensor is designed to be used in smaller duct applications and includes an insulation pad for sealing your duct and dampening vibration. The sensor length should be determined by the width or diameter of your duct such that the tip of the probe reaches the approximate center of the duct. Our standard enclosure options are the galvanized enclosure “-GD” or plastic duct enclosure with hinged cover “-PB”. On larger ducts, you may want to refer to our Rigid or Bendable Copper Averaging sensor for increased sensing points and better temperature control. This series can be ordered with optional NEMA/IP rated weather proof enclosures and NIST certificates as referenced on the back of the product data sheet. Applications: Roof Top Units, Air Handlers, Supply/Discharge/Return/Mixed Air Temperatures
$95.70
The ACI Thermistor Duct Series features a stainless steel probe with two, 22 AWG Etched Teflon colored lead wires to differentiate the different sensor types. The sensors in this series are manufactured using ACI’s proved double encapsulation process to eliminate the effects of moisture on the sensors and increased response times from our high quality, thermally conductive epoxy. The duct sensor is designed to be used in smaller duct applications and includes an insulation pad for sealing your duct and dampening vibration. The sensor length should be determined by the width or diameter of your duct such that the tip of the probe reaches the approximate center of the duct. Our standard enclosure options are the galvanized enclosure “-GD” or plastic duct enclosure with hinged cover “-PB”. On larger ducts, you may want to refer to our Rigid or Bendable Copper Averaging sensor for increased sensing points and better temperature control. This series can be ordered with optional NEMA/IP rated weather proof enclosures and NIST certificates as referenced on the back of the product data sheet. Applications: Roof Top Units, Air Handlers, Supply/Discharge/Return/Mixed Air Temperatures
$90.20
The ACI Thermistor Duct Series features a stainless steel probe with two, 22 AWG Etched Teflon colored lead wires to differentiate the different sensor types. The sensors in this series are manufactured using ACI’s proved double encapsulation process to eliminate the effects of moisture on the sensors and increased response times from our high quality, thermally conductive epoxy. The duct sensor is designed to be used in smaller duct applications and includes an insulation pad for sealing your duct and dampening vibration. The sensor length should be determined by the width or diameter of your duct such that the tip of the probe reaches the approximate center of the duct. Our standard enclosure options are the galvanized enclosure “-GD” or plastic duct enclosure with hinged cover “-PB”. On larger ducts, you may want to refer to our Rigid or Bendable Copper Averaging sensor for increased sensing points and better temperature control. This series can be ordered with optional NEMA/IP rated weather proof enclosures and NIST certificates as referenced on the back of the product data sheet. Applications: Roof Top Units, Air Handlers, Supply/Discharge/Return/Mixed Air Temperatures
$134.20
The ACI Thermistor Immersion Series features a ¼” diameter stainless steel probe with two, 14 inch 22 AWG Etched Teflon colored lead wires depending on the probe length ordered to differentiate the different sensor types. The sensors in this series are manufactured using ACI’s proven double encapsulation process to eliminate the effects of moisture and to increase the response times using our high quality, thermally conductive epoxy. The immersion sensors include a welded thermowell “-I” version but can be ordered without the welded thermowell “-INW” version. The “INW” version includes a standard ½” NPS Male process thread to be used with an optional machined thermowell or in an existing thermowell application. Optional NEMA/IP rated enclosures and NIST certificates are available the back of the product data sheet. Applications: Chilled Water Systems, Hot Water Systems, Boilers, Pumps, Compressor, Chillers
$217.80
The ACI Thermistor Freezer Series features a 3/16” diameter stainless steel probe with a 30 Foot, 3 Conductor, 24 AWG Jacketed Teflon Cable. The sensors in this series are manufactured using ACI’s proven encapsulation process to eliminate the effects of moisture upon the sensors. The probe is designed to be used in a Refrigerated, Freezer or Hydronic applications where a remote sensor must be used. An optional NEMA 4X rated weatherproof enclosure and NIST Certificate is available as referenced in the ordering grid on the back of the product data sheet. Applications: Pharmaceutical, Refrigerators, Freezers, Hydronic Heating, Remote Sensor Applications
$91.30
The ACI Thermistor Bullet Probe Series features a one-inch stainless steel probe with two, 24-inch 22 AWG Etched Teflon colored lead wires to differentiate NTC sensor types. The sensors in this series are manufactured using ACI’s proven double encapsulation process to eliminate the effects of moisture upon the sensors and to increase the thermal response times using our high quality, thermally conductive epoxy. The bullet style sensor is designed to monitor air temperatures and should not be fully submerged in water. This series can be ordered with different wire options and NIST certificates.
$174.90
The polycarbonate NEMA 4X, immersion configuration is designed for wet environments and adds a level of corrosion resistance.  It has male 1/2 inch NPT threads and the sensing element is double encapsulated to avoid sensor failures caused by moisture infiltration.  ACI also standardizes with etched Teflon lead wires and a two part well is included with this configuration. ACI immersion temperature sensors are designed for HVAC, Building Automation Systems, and light industrial applications. Specific applications include: chillers, hot water systems, tanks, and boilers. NOTE: Welded thermowells are not intended for moving water or high pressure service. Fluid velocity and wake frequency are primary factors in well failure. Machined thermowells should be used in these types of applications. 
$204.60
The ACI Thermistor Freezer Series features a 3/16” diameter stainless steel probe with a 30 Foot, 3 Conductor, 24 AWG Jacketed Teflon Cable. The sensors in this series are manufactured using ACI’s proven encapsulation process to eliminate the effects of moisture upon the sensors. The probe is designed to be used in a Refrigerated, Freezer or Hydronic applications where a remote sensor must be used. An optional NEMA 4X rated weatherproof enclosure and NIST Certificate is available as referenced in the ordering grid on the back of the product data sheet. Applications: Pharmaceutical, Refrigerators, Freezers, Hydronic Heating, Remote Sensor Applications
$90.20
The ACI Thermistor Duct Series features a stainless steel probe with two, 22 AWG Etched Teflon colored lead wires to differentiate the different sensor types. The sensors in this series are manufactured using ACI’s proved double encapsulation process to eliminate the effects of moisture on the sensors and increased response times from our high quality, thermally conductive epoxy. The duct sensor is designed to be used in smaller duct applications and includes an insulation pad for sealing your duct and dampening vibration. The sensor length should be determined by the width or diameter of your duct such that the tip of the probe reaches the approximate center of the duct. Our standard enclosure options are the galvanized enclosure “-GD” or plastic duct enclosure with hinged cover “-PB”. On larger ducts, you may want to refer to our Rigid or Bendable Copper Averaging sensor for increased sensing points and better temperature control. This series can be ordered with optional NEMA/IP rated weather proof enclosures and NIST certificates as referenced on the back of the product data sheet. Applications: Roof Top Units, Air Handlers, Supply/Discharge/Return/Mixed Air Temperatures