DIN Signal transmitters for load cell, process, pulse and temperature

DIN Signal transmitters for load cell, process, pulse and temperature

High precision signal transmitters which are PC-programmable and only 22.5mm wide. We can also supply them pre-configured for you, so you only need to connect.

They are ideal for use in most industrial measurements, catering for 4 or 6 wire load cells, 4-20mA and 0-10V process signals, DC voltages up to 600V and DC current up to 5A.

New: Ex nR Atex Certified build options available

For hazardous areas we can offer the following explosion proof options on most models. Tell us what you need and we will be pleased to quote for Atex certified systems

  • Zone 1 ii 2 G Ex px iiC T6/T5/T4 Gb – Requires pressurised air system
  • Zone 2 ii 3 G Ex nR iiC T6/T5/T4 Gc – any product
  • EXD Zone 2 on request – POA

The London Electronics ATEX certified products are supplied certified for use in the condition in which they are supplied. No liability will be assumed for any loss or damages of any nature, direct or indirect, including any loss of profits or consequential damages, injury or death suffered or incurred by the buyer as a consequence of failure to install, use and/or apply the product within the scope of the installation document and certification supplied.

They also include pulse input versions for total, rate, period, phase angle and quadrature.

LT Series, made in USA

Load Cell input transmitter with 4-20 mA, 2 alarm & RS232/RS485 output
4 or 6 wire load cell connection. 10v 120mA Excitation supply.
5V at 100mA is user selectable.
LT20-WM1 = 85-265V AC, standard software
LT21-WM1 = 10-48V DC, standard software

DC input transmitter (4-20mA, 0-10V, 1-5V, 5A, 600V) with 4-20 mA, 2 alarm & RS232/RS485 output
5 selectable voltage input ranges from 0-200mV to 0-600V and
4 selectable current input ranges from 0-2mA to 0-5A
LT20-P = 85-265V AC, standard software
LT21-P = 10-48V DC, standard software

PT100 input transmitter with 4-20 mA, 2 alarm & RS232/RS485 output
LT20-385C = 85-265V AC, standard software
LT21-385C = 10-48V DC, standard software

Pulse input rate/total transmitter with 4-20 mA, 2 alarm & RS232/RS485 output
LT60-FR = 85-265V AC, standard software
LT61-FR = 10-48V DC, standard software

Serial input RS232/485 transmitter with 4-20 mA, 2 alarm & RS232/RS485 output
LTS60 = 85-265V AC, standard software
LTS61 = 10-48V DC, standard software

Thermocouple input transmitter with 4-20 mA, 2 alarm & RS232/RS485 output
LT20-KC = 85-265V AC, standard software
LT21-KC = 10-48V DC, standard software

Change suffix to suit different thermocouple types…
EC = Type E, Celcius
JC = Type J, Celcius
KC = Type K, Celcius
NC = Type N, Celcius
RC = Type R, Celcius
SC = Type S, Celcius
TC = Type T, Celcius



Common Specifications

Analogue Output (standard)
Output Levels 4-20 mA, 0-20 mA, 0-10 Vdc, -10 to +10Vdc (user selectable)
Compliance at 20 mA 10V (0-500Ω load)
Compliance at 10V 2 mA (5 kΩ or higher load)
Output Resolution 16 bits (65,536 steps)
Output Accuracy 0.02% of output span plus conversion accuracy
Output Isolation 250V rms working, 2.3 kV rms per 1 minute test
Step response time 50 ms
Serial Data Output (standard)
Signal Types RS232 or RS485 (half or full duplex), jumper selectable
Data Rates 300, 600, 1200, 2400, 4800, 9600, 19200 baud
Output Isolation 250V rms working, 2.3 kV rms per 1 min test
Serial Protocols Modbus RTU, Modbus ASCII, Laurel ASCII
Modbus Compliance Modbus over Serial Line Specification V1.0 (2002)
Ethernet Connector RJ45 jack for 10/100 Base-T Ethernet cable
RS232/485 Connector Screw terminals for easy daisy chaining
Digital Addresses 247 for Modbus, 31 for Laurel ASCII
Dual Relay Output (standard)
Relay Type Two solid state relays, SPST, normally open, Form A
Load Rating 120 mA at 140 Vac or 180 Vdc
Power Input
Standard Power 85-264 Vac or 90-300 Vdc (DC operation not ETL certified)
Low Power Option 10-48 Vdc or 12-32 Vac
Power Frequency DC or 47-63 Hz
Power Isolation 250V rms working, 2.3 kV rms per 1 min test
Power Consumption 2W typical
Dimensions 129 x 104 x 22.5 mm case
Mounting 35 mm rail per DIN EN 50022
Electrical Connections Plug-in screw-clamp connectors
Operating Temperature 0°C to 55°C
Storage Temperature -40°C to 85°C
Relative Humidity 95% at 40°C, non-condensing
Cooling Required Mount transmitters with ventilation holes at top and bottom. Leave 6 mm (1/4") between transmitters, or force air with a fan.

Programming the transmitters

We offer free setup software for use on Windows PCs. You will need a cable from your PC to the RS232 port of the transmitter.

We offer a direct RS232>Transmitter cable, model CBL04, or, if your PC doesn’t have an RS232 port, you can use our CBL02 USB>RS232 converter cable in addition to the CBL04 cable.

You can download the setup software [here]

Triple 4-20mA loop splitter – TIM018-Mk2

Improve the security of your distributed 4-20mA loops. Designed and built by us in the UK. The TIM018-Mk2 takes one 4-20mA input and splits it 3 ways. Each output loop can be scaled separately.

This new version of the TIM018 has these improvements over the previous model …

1. Narrower case, allows denser packing
2. Wide range power supplies cover 95-265 VAC or 11-30VDC
3. Adjustments from the front panel
4. Detachable screw terminal connectors

All loops are load-isolated, so that a problem on one loop won’t affect the others.

Look at the diagram below, here you see one transmitter feeding 4 receivers, all connected in series. If the line is broken, all devices loose their signal.

Now look at the system with the TIM018 triple loop splitter included. If any of the receivers on the outputs of the TIM018 are disconnected, the other loops will still function correctly.

Self powered 4-20 mA loop isolator P17G

The P17G is a compact, high precision loop isolator, made in Poland, which does not need an external supply. It takes its power from the 4-20mA input signal.


Conversion error +/- 0.2% of the range
Thermal error +/- (0.05 % of range /10C)
Load error +/- (0.15 % range/100 Ohms)
Conversion bandwidth 70 Hz
Isolation 500V DC - 50Hz 1 minute
Operating temperature -20 to 55oC
Storage temperature -25 to +85oC
Humidity <95% non condensing
Operating position any
Sustained overload capacity 40mA
Sealing IP50 (housing) / IP20 (electrical
Weight 80 g
Mounting DIN rail acc. to EN 60715
Analog input 4...20 mA
Input voltage drop Iin x Rload out x 1.25
Output load (Rload) < 500 Ohms
Installation category III
Pollution grade 2