RTD Alarms and Transmitters

• Lifetime 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

Click on PDF links below
for product information

Literature and Links

API product brochure
Options & accessories
Cross reference
Regulatory Compliance page

UL Approvals

API modules USA
API modules Canada

APD modules USA
APD modules Canada

Reference Info

Sink or Source
LoopTracker and Output Test
Signal Conditioner Terminology
Industry Terminology
RFI & EMI
Ohm's Law
What is a Ground Loop?
Installation FAQs

Applications

Dam Bubbler
Measure Heat Exchanger Δ Temperature
Control Heat Exchanger Δ Temperature
Chiller Temperature
Bearing Temperature
Motor Temperature
Motor Overheating
Motor Bearings

How to Order

1. Select a model
2. See data sheet for ordering info and options
3. Note that options affect pricing
4. Request a quote via chat or call us
5. 2-5 day typical lead time + shipping time
6. 5-10 day lead time for quantities of 5 or more + shipping time
7. To place your order

• Call 800-942-0315 for credit card order
• Find your authorized representative
• Call us to find your local distributor
• Set up an account to use a purchase order
• Outside the USA?

RTD Input Alarm Trips

Factory Configured

APD 1400  from $289
APD 1420  from $309

Open Datasheet
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Specify RTD type and temperature range
Factory configured
10 Ω to 2000 Ω RTD including
100 Ω: 0.00385α, 0.00391α,
10 Ω Cu, 1000 Ω Ni-Fe,
120 Ω Ni or Special
APD 1400 Single Alarm Trip
Dual SPDT contact sets
Standard: HI alarm, non-latching, normal acting
See data sheet for alarm options
APD 1420 Dual Alarm Trip
2 independent SPDT contact sets
Standard: HI/LO alarms, non-latching, normal acting
See data sheet for alarm options

• 2-wire or 3-wire RTD
• Lead wire compensation for 3-wire
• User adjustable setpoint(s)
• User adjustable deadband(s)
• 8 Amp SPDT contacts
• Input LoopTracker LED
• Alarm status LEDs
• Alarm options: LO, HI/HI, LO/LO
• Optional reverse acting
• Optional latching alarms
• Push to test/reset
• Remote push to test/reset
• Full I/O/power isolation
• Removable plugs
• DIN rail mount without tools
• Universal power 85-265 VAC, 60-300 VDC
• D option for 9-30 VDC, 10-32 VAC power

RTD Input Alarm Trips

Factory Configured

API 1400 G  from $279
API 1420 G  from $299

Open Datasheet
Download Datasheet

Specify RTD type and temperature range
Factory configured
10 Ω to 2000 Ω RTD including
100 Ω: 0.00385α, 0.00391α,
10 Ω Cu, 1000 Ω Ni-Fe,
120 Ω Ni or special
API 1400 G Single Alarm Trip
One DPDT contact set
Standard: HI alarm, normal acting,
adj. deadband, non-latching
See data sheet for alarm options
API 1420 G Dual Alarm Trip
Two SPDT contact sets
Standard: HI/LO alarms, normal acting,
1% deadband, non-latching
See data sheet for alarm and deadband options

• User adjustable setpoint(s)
• 2-wire or 3-wire RTD
• Lead wire compensation for 3-wire
• 8 Amp contacts
• Hot-swappable plug-in design
• Input LoopTracker LED
• Alarm status LEDs
• Alarm options: LO, HI/HI, LO/LO
• Optional reverse acting
• Optional latching alarms
• Output test button
• Uses API-011 11-pin socket
• 115 VAC powered
• A230 option for 230 VAC
• P option for 85-265 VAC, 60-300 VDC power
• D option for 9-30 VDC power

RTD to DC Isolated Transmitter

Factory Configured

APD 4001  from $375

Open Datasheet
Download Datasheet

Specify RTD type and temperature range
10 Ω to 2000 Ω RTD including
100 Ω: 0.00385α, 0.00391α,
10 Ω Cu, 1000 Ω Ni-Fe,
120 Ω Ni or special
Specify output range
0-1 V to 0-10 V
±1 V to ±10 V
0-1 mA to 0-20 mA, 4-20 mA

• RTD linearization
• Removable plugs
• I/O LoopTracker LEDs
• Output test button
• Full I/O/power isolation
• 2-wire or 3-wire RTD
• Lead wire compensation for 3-wire
• DIN rail mount
• Universal power 85-265 VAC, 60-300 VDC
• D option for 9-30 VDC, 10-32 VAC power

Universal Temperature Input to DC Isolated Transmitter

Field Programmable

APD 4000  from $375

Open Feature Summary
Download Feature Summary
Open Datasheet
Download Datasheet

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

• 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
• For orders of 5 or more, call us for lead times

Universal Input to DC Isolated Signal Conditioner

Field Programmable

APD 8000  from $399

Open Feature Summary
Download Feature Summary
Open Datasheet
Download Datasheet

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 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
• For orders of 5 or more, call us for lead times

RTD or Thermistor Input to DC Isolated Transmitter

Factory Configured

APD 4002  from $375

Open Datasheet
Download Datasheet

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

Universal RTD to DC Isolated Transmitter

Field Programmable

APD 4151  from $395

Open Datasheet
Download Datasheet

Field programmable input
RTD: 2, 3, or 4 wire, 10 Ω to 8000 Ω RTD
Custom input available
18 field selectable output ranges
Voltage: 0-1V, 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

• 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
• For orders of 5 or more, call us for lead times

RTD to DC Isolated Transmitter

Factory Configured

API 4001 G L  from $409

Open Datasheet
Download Datasheet

Specify RTD type and temperature range
Factory configured
10 Ω to 2000 Ω RTD including
100 Ω: 0.00385α, 0.00391α
10 Ω Cu, 1000 Ω Ni-Fe,
120 Ω Ni or special
Specify output range
Factory configured
0-1 V to 0-10 V
±1 V to ±10 V
0-1 mA to 0-20 mA, 4-20 mA

• RTD linearization
• Hot-swappable plug-in design
• I/O LoopTracker LEDs
• Output test button
• Full I/O/power isolation
• 2-wire or 3-wire RTD
• Lead wire compensation for 3-wire
• Uses API-008 8-pin socket
• 115 VAC powered
• A230 option for 230 VAC
• P option for 85-265 VAC, 60-300 VDC power
• D option for 9-30 VDC power

Differential RTD to DC Transmitter

Factory Configured

API 4001 G SA-B  from $409

Open Datasheet
Download Datasheet

Specify temperature range
Factory configured
Two 100 Ω 0.00385α RTDs
ΔT from 20F° to 900F° or
10C° to 500C°
Specify output range
Factory configured
0-1 V to 0-10 V
±1 V to ±10 V
0-1 mA to 0-20 mA, 4-20 mA

• Hot-swappable plug-in design
• I/O LoopTracker LEDs
• Output test button
• 2-wire or 3-wire RTD
• Lead wire compensation for 3-wire
• Linearized RTD
• Inputs can be field calibrated
• Uses API-011 11-pin socket
• 115 VAC powered
• A230 option for 230 VAC
• P option for 85-265 VAC, 60-300 VDC power
• D option for 9-30 VDC power

Universal Input to 4-20 mA Loop Powered Transmitter

Field Programmable

K121  $149 *in stock*

Open Datasheet
Download Datasheet
Open Installation Manual
Download Installation Manual
Click to see ALL Seneca products

Field Programmable Input
Input: –150 mV to +150 mV
–30 V to +30V
–24 mA to 24 mA
RTD: Pt100, Pt500, Pt1000, Ni100
Thermocouple: J, K, T, E, R, S, B, N
Potentiometer: 500 Ω to 10 KΩ
Resistance: 1750 Ω
Output: 4-20 mA loop powered
Powered by the output loop

• Only 6.2 mm wide
• PC programmable configuration
• Full 2-way isolation
• Low cost
• DIN rail mount without tools
• Powered by 4-20 mA loop

100 Ω RTD to DC Isolated Transmitter

Field Configurable

K109PT  $169 *in stock*

Open Datasheet
Download Datasheet
Open Installation Manual
Download Installation Manual
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Field Configurable Input
Input: One 100 Ω RTD, 385 Curve RTD, 2, 3, or 4 wire
–150 to 650°C, (–238 to 1202°F), 50°C min. span
Field Configurable Output
Output: 4-20 mA, 0-20 mA, 20-4 mA, 20-0 mA,
0-5 V, 1-5 V, 0-10 V, 10-0 V

• Only 6.2 mm wide
• DIP switch configuration
• Full 3-way isolation
• Low cost
• DIN rail mount without tools
• Power: 19.2-30 VDC or K-SUPPLY+KBUS

Universal Temperature to DC Isloated Transmitter

Field Programmable

Sineax V624

Open Datasheet
Download Datasheet
Open Installation Manual
Download Installation Manual
Download Software

T/C types
J, K, T, E, R, S, N, B, W5, W3, L, U
RTD, 2-, 3-, or 4-wire
100 Ω 0.00385α
100 Ω 0.003916α
Thermistor
Software for custom input linearization
Specify if Current or Voltage Output
0-2 mA to 0-20 mA, 20-0 mA
0-1 V to 0-10 V, 10-0 V

• PC Programmable
• Reverse Output Programmable
• Custom Input Linearization
• Programmable Sensor Fault Response
• Removable Plugs
• 3.7 kV Input/Output/Power Isolation
• 24-60 or 85-230 VAC/VDC Powered
• 3 Year Warranty

IsoSplitter ^® Signal Splitter
1 RTD Input to 2 DC Outputs

Factory Configured

APD 1393  from $499

Open Datasheet
Download Datasheet

Specify RTD type and temperature range
Factory configured
10 Ω to 2000 Ω RTD including
100 Ω 0.00385α
100 Ω 0.00391α,
10 Ω Cu
1000 Ω Ni-Fe
120 Ω Ni or special
Specify output range for each channel
2 independent channels
0-1 V to 0-20 V
±1 V to ±10 V
0-1 mA to 0-25 mA, 4-20 mA

• One RTD input
• Two independent DC output channels
• I/O LoopTracker LEDs
• Selectable sink/source mA output
• 20 V output loop power supplies
• Output test buttons
• Full I/O/power isolation
• Removable plugs
• DIN rail mount
• 45 mm wide
• Universal power 85-265 VAC, 60-300 VDC
• D for 9-30 VDC, 10-32 VAC power

DuoPak ^® 2 Channel Isolated Signal Conditioners

Factory Configured

APD 2000 Series  from $519

Specify input range for each channel
APD 2001 Ch1: DC mV/V/mA Ch2: RTD
APD 2011 Ch1: RTD Ch2: RTD
APD 2013 Ch1: RTD Ch2: Potentiometer
APD 2015 Ch1: RTD Ch2: Strain gauge
APD 2016 Ch1: RTD Ch2: AC mV/V/mA
APD 2017 Ch1: RTD Ch2: Frequency
Specify output range for each channel
2 independent channels
0-1 V to 0-20 V
±1 V to ±10 V
0-1 mA to 0-25 mA, 4-20 mA

• Optional I/O reversal
• I/O LoopTracker LEDs
• Selectable sink/source mA output
• 20 V output loop power supplies
• Output test buttons
• Full I/O/power isolation
• Removable plugs
• DIN rail mount
• 45 mm wide
• Universal power 85-265 VAC, 60-300 VDC
• D for 9-30 VDC, 10-32 VAC power

ThermoPro ^®
Battery Powered RTD Temperature Indicator

Field Configurable

T16B   $389
T16BBL: Backlit display  $419

Open Datasheet
Download Datasheet

T16BBL: Backlit display

• Specify RTD length
• Specify fixed or spring-loaded RTD
• Use spring-loaded for a thermowell
• Specify default temperature units
  • –58.0°F to 392.0°F or
  • –50.0°C to 200.0°C or
  • 223.0 K to 473.0 K
• Choose auto shutoff time
  • -5 five minutes (default if not specified)
  • -10 ten minutes
  • -30 thirty minutes
  • -ON on/off only
• See data sheet for complete model numbers

• Battery life to 1000 hrs
• BL red LED display backlight battery life up to 750 hrs
• Includes 2 AA batteries
• Configurable auto shutoff time
• Selectable °F, °C or K
• Selectable auto shutoff time
• Configurable min/max memory
• Able to retain min/max if power is off
• Pass code protected setup and calibration

ThermoPro ^®
Loop Powered Indicating RTD Transmitter

Field Configurable

T16L   $389

Open Datasheet
Download Datasheet

• Specify RTD length
• Specify fixed or spring-loaded RTD
• Use spring-loaded for a thermowell
• Specify temperature range of output
  • –58.0°F to 392.0°F or
  • –50.0°C to 200.0°C or
  • 223.0 K to 473.0 K
• See data sheet for complete model numbers

• 2-wire design
• Powered by 8-32 VDC 4-20 mA current loop
• User-programmable 4-20 mA output range
• Selectable °F, °C or K
• Pass code protected setup and calibration
• Old model number: F16LT

ThermoPro ^®
Indicating RTD Temperature Alarms

Field Configurable

T16ADA   $479
T16ADABL: Backlit display  $499

Open Datasheet
Download Datasheet

• Specify RTD length
• Specify fixed or spring-loaded RTD
• Use spring-loaded for a thermowell
• Specify default temperature units
  • –58.0°F to 392.0°F or
  • –50.0°C to 200.0°C or
  • 223.0 K to 473.0 K
• See data sheet for complete model numbers

• User-programmable alarms
  • User-programmable alarm logic
  • User-programmable setpoints
  • 2 SPDT relays
  • 1A@24 VDC, or 0.5A@115VAC, non-inductive
• Selectable °F, °C, or K temperature units
• Powered by 8-32 VDC, 10-32 VAC
• User configurable relay operation
• Push to test alarms
• Pass code protected setup and calibration

Head-Mount RTD Transmitter, Non-Isolated

Field Programmable

Fits DIN Form B Heads

T120  $89 *in stock*

Open Datasheet
Download Datasheet
Open Installation Manual
Download Installation Manual
Click to see ALL Seneca products

Programmable
Input: Pt100 or Ni100 RTD
2, 3, or 4 wire
Selectable Output
Output: 4-20 mA, 20-4 mA

• Order T120-C and specify I/O for pre-programmed model
• 44 mm dia
• EASY-USB configuration
• Low cost
• DIN B mount with 5.8 mm (0.228" dia) center hole
• Power: 19.2 to 30 VDC current loop

Head-Mount Universal Transmitter, Isolated

Field Programmable

Fits DIN Form B Heads

T121  $159 *in stock*

Open Datasheet
Download Datasheet
Open Installation Manual
Download Installation Manual
Click to see ALL Seneca products

Programmable
Input: Pt100 or Ni100, Pt500, Pt1000
J, K, R, S, T, B, E, N
Potentiometer
mVDC, VDC
Selectable Output
Output: 4-20 mA, 20-4 mA

• Order T121-C for pre-programmed I/O
• 44 mm dia
• EASY-USB configuration
• I/O isolation
• Low cost
• DIN B with 5.8mm (0.228"dia) center hole
• Power: 7 to 30 VDC current loop

USB - UART TTL Converter

EASY-USB  $109

*in stock*
Open Datasheet
Download Datasheet
Open Installation Manual
Download Installation Manual
EASY-USB Software Link

Programming kitK121
K121

Includes
Converter
Software mini CD (or download latest)
Adapter cable (std USB cable not included)

4 Digit 4-20 mA Loop Powered Display

Field Rangeable

S315  $139 *in stock*
S315-IP66  $300

Open Datasheet
Download Datasheet
Open Installation Manual
Download Installation Manual
Click to see ALL Seneca products

Loop Powered Display
Input: 4-20 mA
Display: 4 digit red LED

• 1/8 DIN panel mount or IP66 housing
• Scaleable 4 digit display