Thermistor Transmitters

  • 6 Year Warranty on API Modules
  • LoopTracker® LEDs
  • Hot-Swappable Plug-In Design
  • Zero and Span Transmitter Output Calibration
  • Push to Test Output
  • Full I/O/Power Isolation
Product brochure
Options & accessories
Regulatory compliance

Click on PDF links below
for product information
Reference Info
Sink or Source
LoopTracker and Output Test
Signal Conditioner Terminology
Industry Terminology
Ohm's Law
What is a Ground Loop?

Dam Bubbler
How to select your product
  • Open pdf datasheet for your model
  • Select model, range, units, options, accessories
  • Contact us if you need assistance
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Model Input/Output Features Product

RTD or Thermistor Input Alarm Trips

Factory Configured

APD 1401  from $379
APD 1421  from $399

Open Datasheet
Download Datasheet
RTD: specify type, 2, 3 or 4 wire, and temperature range
Factory configured
10 Ω to 2000 Ω RTD including
100 Ω: 0.00385α, 0.003916α, 0.00392α,
10 Ω Cu, 1000 Ω Ni-Fe,
120 Ω Ni or Special

Thermistor: specify type and temperature range.
For other sensor types provide temperature-resistance chart.

Factory configured
44004/44033 2.252 kΩ at 25°C
44005/44030 3.000 kΩ at 25°C
44007/44034 5.000 kΩ at 25°C
44006/44031 10.00 kΩ at 25°C
44008/44032 30.00 kΩ at 25°C
YSI 400 2.252 kΩ at 25°C
Spectrum 1003k 1 kΩ

APD 1401 Single Alarm Trip
Dual DPST contact sets
Standard: HI alarm, non-latching, normal acting

APD 1421 Dual Alarm Trip
Two DPST contact sets
Standard: HI/LO alarms, normal acting,
two set/reset adjustments, non-latching

See data sheet for alarm options

  • New microprocessor-based version
    • Complete RTD or thermistor selection
    • Microprocessor controlled input linearization
    • More burnout options
    • Improved setpoint/reset point control
  • 2-, 3-, or 4-wire RTD
  • Lead wire compensation for 3-, or 4-wire
  • User adjustable set and reset point(s)
  • 8 Amp contacts
  • Removable plugs for easier installation
  • Input LoopTracker LED and output test button
  • Alarm status LEDs
  • Alarm options: LO, HI/HI, LO/LO, band alarm
  • Optional reverse acting, optional latching
  • DIN rail mount without tools
  • Universal power 85-265 VAC, 60-300 VDC
  • D option for 9-30 VDC, 10-32 VAC power

APD 1421
APD 1401, APD 1421

Universal Input to DC Isolated Signal Conditioner

Field Programmable

APD 8000  from $529

*Free I/O Range Setup*
Include your I/O ranges on your order,
and we'll set it up for you!

Open Datasheet
Download Datasheet

Open Feature Summary
Download Feature Summary
Field configurable inputs
DC volts: 35 ranges from ±25mVDC to ±10 VDC
DC mA sinking input, 20 ranges from ±0.5mADC to ±20mADC
Potentiometer: 100Ω min. to 1 MegaΩ max.
Thermocouple: J, K, T, E, R, S, N, B, C, D, G, M, P
RTDs: 2, 3, or 4 wire, 10Ω to 8000Ω RTDs
Thermistor: 44000 series, YSI 400, Spectrum
Custom input available

18 field programmable output ranges
Voltage: 0-1V, 0-2V, 0-4V, 0-5V, 1-5V, 0-8V, 0-10V, 2-10V,
±5V, ±10V
Current: 0-2mA, 0-4mA, 0-8mA, 0-10mA, 2-10mA, 0-16mA,
0-20mA, 4-20mA
Can be wired for sink or source
  • Switch and pushbutton setup
  • Removable plugs
  • Input LoopTracker LED
  • Output test button
  • Full I/O/power isolation
  • Selectable sink/source output
  • 20 V output loop power supply
  • Universal power 85-265 VAC, 60-300 VDC
  • D option for 9-30 VDC, 10-32 VAC power
  • For orders of 5 or more, call us for lead times

APD8000UL approved
APD 8000