Signal Conditioners, Converters,  Isolators, Transmitters

lifetime warranty
  • Lifetime Warranty on API and APD Modules
  • LoopTracker® LEDs
  • Hot-Swappable Plug-In Design
  • Zero and Span Output Calibration
  • Push to Test Output
  • Full I/O/Power Isolation
Click on model numbers below
for data sheets

Literature and Links

API product brochure

Options & accessories

UL Approvals

APD modules USA
APD modules Canada

Reference Info

Ground Loops
RFI / EMI
LoopTracker and Output Test
Sink vs Source

How to Order
  1. Select a model
  2. See data sheet for ordering info and power options
  3. See Price list
  4. 2-5 day typical lead time (USA customers)
  5. To place your order
Model Input/Output Features Product
Universal Input to DC Signal Conditioners
Field Programmable I/O
DIN Style


APD 8000 Features

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

18 field programmable output ranges
Voltage: 0-1 V, 0-2 V, 0-4 V, 0-5 V, 1-5 V, 0-8 V, 0-10 V, 2-10 V, ±5 VDC, ±10 VDC
Current: 0-2 mA, 0-4 mA, 0-8 mA, 0-10 mA, 2-10 mA, 0-16 mA, 0-20 mA, 4-20 mA
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 output sink/source
  • 20 V output loop power supply
  • Universal power 85-265 VAC, 60-300 VDC
  • D option for 9-30 VDC, 10-32 VAC power

APD8000 UL approved
APD 8000
Universal Temperature Input to DC Signal Conditioners
Field Programmable I/O
DIN Style

APD 4000 Feature Summary

APD 4000 Datasheet
Field programmable inputs
Thermocouples: J, K, T, E, R, S, N, B, C, D, G, M, N, P
RTDs: 2, 3, or 4 wire, 10 Ω to 8000 Ω RTDs
Thermistors: 44000 series, YSI 400, Spectrum
Custom input available

18 field selectable output ranges
Voltage: 0-1 V, 0-2 V, 0-4 V, 0-5 V, 1-5 V, 0-8 V, 0-10 V, 2-10 V, ±5 VDC, ±10 VDC
Current: 0-2 mA, 0-4 mA, 0-8 mA, 0-10 mA, 2-10 mA, 0-16 mA, 0-20 mA, 4-20 mA
Can be wired for sink or source
  • Covers all common temperature sensors
  • Removable plugs
  • Input LoopTracker LED
  • Output test button
  • Full I/O/power isolation
  • Selectable output sink/source
  • 20 V output loop power supply
  • Universal power 85-265 VAC, 60-300 VDC
  • D option for 9-30 VDC, 10-32 VAC power

APD4000 UL approved
APD 4000
RTD or Thermistor Input to DC Isolated Transmitter
Factory Configured
DIN Style

APD 4002
Factory set input range
RTD: 2, 3, or 4 wire, 10 Ω to 8000 Ω RTD
Thermistor: 44000 series, YSI 400, Spectrum
Custom input available

Factrory set output range
Voltage: 0-1 V to 0-10 V, ±5 V, ±10 V
Current: 0-2 mA to 4-20 mA
Can be wired for sink or source
  • Covers all common RTDs and Thermistors
  • Removable plugs
  • Input LoopTracker LED
  • Output test button
  • Full I/O/power isolation
  • Selectable output sink/source
  • 20 V output loop power supply
  • Universal power 85-265 VAC, 60-300 VDC
  • D option for 9-30 VDC, 10-32 VAC power

APD4002 UL approvedNew!
APD 4002
Thermocouple to DC Isolated Transmitter
Factory Configured
DIN Style

APD 4130
Factory set input range
Thermocouple: J, K, T, E, R, S, N, B, C, D, G, M, N, P
Custom input available

Factrory set output range
Voltage: 0-1 V to 0-10 V, ±5 V, ±10 V
Current: 0-2 mA to 4-20 mA
Can be wired for sink or source
  • ±0.25 % accuracy
  • Removable plugs
  • Input LoopTracker LED
  • Output test button
  • Full I/O/power isolation
  • Selectable output sink/source
  • 20 V output loop power supply
  • Universal power 85-265 VAC, 60-300 VDC
  • D option for 9-30 VDC, 10-32 VAC power

APD4130 UL approvednew!
APD 4130
Thermocouple to DC Isolated Transmitter
High Accuracy

Factory Configured
DIN Style

APD 4131
Factory set input range
Thermocouple: J, K, T, E, R, S, N, B, C, D, G, M, N, P
Custom input available

Factrory set output range
Voltage: 0-1 V to 0-10 V, ±5 V, ±10 V
Current: 0-2 mA to 4-20 mA
Can be wired for sink or source
  • ±0.1 % Accuracy
  • Removable plugs
  • Input LoopTracker LED
  • Output test button
  • Full I/O/power isolation
  • Selectable output sink/source
  • 20 V output loop power supply
  • Universal power 85-265 VAC, 60-300 VDC
  • D option for 9-30 VDC, 10-32 VAC power

APD4131 UL approvednew!
APD 4131
Universal RTD to DC Isolated Transmitter
Field Programmable I/O
DIN Style

APD 4151
Field programmable input
RTD: 2, 3, or 4 wire, 10 Ω to 8000 Ω RTD
Custom input available

18 field selectable output ranges
Voltage: 0-1 V, 0-2 V, 0-4 V, 0-5 V, 1-5 V, 0-8 V, 0-10 V, 2-10 V, ±5 VDC, ±10 VDC
Current: 0-2 mA, 0-4 mA, 0-8 mA, 0-10 mA, 2-10 mA, 0-16 mA, 0-20 mA, 4-20 mA
Can be wired for sink or source
  • Covers all common RTD sensors
  • Removable plugs
  • Input LoopTracker LED
  • Output test button
  • Full I/O/power isolation
  • Selectable output sink/source
  • 20 V output loop power supply
  • Universal power 85-265 VAC, 60-300 VDC
  • D option for 9-30 VDC, 10-32 VAC power

APD4151 UL approvedNew!
APD 4151
Universal Thermistor to DC Isolated Transmitter
Field Programmable I/O
DIN Style

APD 4152
Field programmable input
Thermistor: 44000 series, YSI 400, Spectrum
Custom input available

18 field selectable output ranges
Voltage: 0-1 V, 0-2 V, 0-4 V, 0-5 V, 1-5 V, 0-8 V, 0-10 V, 2-10 V, ±5 VDC, ±10 VDC
Current: 0-2 mA, 0-4 mA, 0-8 mA, 0-10 mA, 2-10 mA, 0-16 mA, 0-20 mA, 4-20 mA
Can be wired for sink or source
  • Covers all common thermistor sensors
  • Removable plugs
  • Input LoopTracker LED
  • Output test button
  • Full I/O/power isolation
  • Selectable output sink/source
  • 20 V output loop power supply
  • Universal power 85-265 VAC, 60-300 VDC
  • D option for 9-30 VDC, 10-32 VAC power

APD4152 UL approvedNew!
APD 4152
Universal Thermocouple to DC Isolated Transmitter
Field Programmable I/O
DIN Style

APD 4351
Field programmable input
Thermocouple: J, K, T, E, R, S, N, B, C, D, G, M, N, P
Custom input available

18 field selectable output ranges
Voltage: 0-1 V, 0-2 V, 0-4 V, 0-5 V, 1-5 V, 0-8 V, 0-10 V, 2-10 V, ±5 VDC, ±10 VDC
Current: 0-2 mA, 0-4 mA, 0-8 mA, 0-10 mA, 2-10 mA, 0-16 mA, 0-20 mA, 4-20 mA
Can be wired for sink or source
  • Covers all common thermocouples
  • Removable plugs
  • Input LoopTracker LED
  • Output test button
  • Full I/O/power isolation
  • Selectable output sink/source
  • 20 V output loop power supply
  • Universal power 85-265 VAC, 60-300 VDC
  • D option for 9-30 VDC, 10-32 VAC power

APD4351 UL approvedNew!
APD 4351
High Accuracy DC to DC Isolated Transmitter
Field Programmable I/O
DIN Style

APD 4381

54 field configurable input ranges
0-50 mVDC to 0-10 VDC
±25 mV to ±10 VDC
0-500 μA to 0-20 mADC
Custom input range available

18 field configurable output ranges
0-1 V to 0-10 VDC
±5 V to ±10 V
0-2 mA to 0-20 mA, 4-20 mA
  • Covers all common DC sensors
  • Removable plugs
  • I/O LoopTracker LEDs
  • Output test button
  • Full I/O/power isolation
  • Selectable I/O sink/source
  • 15 V input loop power supply
  • 20 V output loop power supply
  • Universal power 85-265 VAC, 60-300 VDC
  • D option for 9-30 VDC, 10-32 VAC power

APD 4381 UL approved New!
APD 4381