Thin DIN Signal Conditioners, Converters, Isolators, Transmitters
- 1 Year Warranty on K-Line Modules
- Hot-Swappable Design
- Economical
- Full I/O/Power Isolation
*stock item* normally stocked, but call for number on hand
Quantities available may vary on a daily basisPlease call to confirm quantities and lead time

for product information
Literature and Links
API K-Line product brochure
Seneca accessories and software
Reference Info
Ground Loops
RFI / EMI
Sink vs Source
API K-Line product brochure
Seneca accessories and software
Reference Info
Ground Loops
RFI / EMI
Sink vs Source
How to Order
- Select a model
- See data sheet for ordering info and options
- Note that options affect pricing
- Request a quote via chat or call us
- Stock to 3 week typical lead time (USA customers)
- 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?
Model
Input/Output
Features
Product
DC to DC Isolated Signal Conditioner
Field Configurable
K109UI $169 *stock item*
Open Datasheet
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Open Installation Manual
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Field Configurable Input
Input: 0-20 mA, 4-20 mA,
0-5 VDC, 1-5 VDC, 0-10 VDC, 2-10 VDC,
0-15 VDC, 0-30 VDC
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
Input: 0-20 mA, 4-20 mA,
0-5 VDC, 1-5 VDC, 0-10 VDC, 2-10 VDC,
0-15 VDC, 0-30 VDC
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



K109UI
DC to DC Isolated Transmitter
with Sink/Source Input
Field Configurable
K109S $169 *stock item*
Open Datasheet
Download Datasheet
Open Installation Manual
Download Installation Manual
Click to see ALL Seneca products
Field Configurable Input
Input: 4-20 mA, 0-20 mA, 20-4 mA, 20-0 mA,
0-5 V, 1-5 V, 0-10 V, 10-0 V
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
Input: 4-20 mA, 0-20 mA, 20-4 mA, 20-0 mA,
0-5 V, 1-5 V, 0-10 V, 10-0 V
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



K109S
Universal Input to 4-20 mA Loop Powered Transmitter
Field Programmable
K121 $149 *stock item*
Open Datasheet
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Open Installation Manual
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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
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



K121
Thermocouple to DC Isolated Transmitter
Field Configurable
K109TC $169 *stock item*
Open Datasheet
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Open Installation Manual
Download Installation Manual
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Field Configurable Input
Input: Thermocouple: J, K, T, E, R, S, N, B
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
Input: Thermocouple: J, K, T, E, R, S, N, B
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



K109TC
100 Ω RTD to DC Isolated Transmitter
Field Configurable
K109PT $169 *stock item*
Open Datasheet
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Open 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
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



K109PT
RS-485 to RS-485 or
RS-232 to RS-485
Repeaters/Isolators/Amplifiers
K107A $159
K107B $159
*stock item*
Open Datasheet
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Open Installation Manual
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K107A RS-485 to RS-485
Data X: One RS-485 half duplex
Data Y: One RS-485 half duplex
K107B RS-232 to RS-485
Data X: One RS-232 half duplex
Data Y: One RS-485 half duplex
Data X: One RS-485 half duplex
Data Y: One RS-485 half duplex
K107B RS-232 to RS-485
Data X: One RS-232 half duplex
Data Y: One RS-485 half duplex
- 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




K107A K107B
USB - UART TTL Converter
EASY-USB $109 *stock item*
Open Datasheet
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Open Installation Manual
Download Installation Manual
EASY-USB Software Link
Programming kitK121
K121
K121
Includes
Converter
Software mini CD (or download latest)
Adapter cable (std USB cable not included)
Converter
Software mini CD (or download latest)
Adapter cable (std USB cable not included)

EASY-USB
K-SUPPLY and KBUS Power Supply
for K-Series Modules
K-SUPPLY $89
*stock item*
KBUS $15
*stock item*
Open Datasheet
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Open Installation Manual
Download Installation Manual
Click to see ALL Seneca products
Regulated Power Distribution
Input: 19.2 to 30 VDC
Output: 19.2 to 30 VDC
Input: 19.2 to 30 VDC
Output: 19.2 to 30 VDC
- Only 6.2 mm wide
- Power supply distribution
- Regulated and isolated
- Low cost
- DIN rail mount without tools
- Power: any 19.2-30 VDC supply



K-SUPPLY K-BUS
4 Digit 4-20 mA Loop Powered Display
Field Rangeable
S315 $139
*stock item*
S315-IP66 $300
Open Datasheet
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Open Installation Manual
Download Installation Manual
Click to see ALL Seneca products
Loop Powered Display
Input: 4-20 mA
Display: 4 digit red LED
Input: 4-20 mA
Display: 4 digit red LED
- 1/8 DIN panel mount or IP66 housing
- Scaleable 4 digit display


S315