Analogue Sensor Controller

RD series

This model has been discontinued.
Compliance with the certification standard is ensured as of the time of shipment from our company.

Main Unit, RS-232C Type RD-50RK

RD-50RK - Main Unit, RS-232C Type

*Please note that accessories depicted in the image are for illustrative purposes only and may not be included with the product.

Data Sheet (PDF)





Measurement function

DC voltage measurement, DC current measurement

A/D converting system

Successive comparison

Measurement range

±5 VDC, ±10 VDC, 4 to 20 mA DC (selectable)

Display range

-19999 to +39999

Measurement accuracy

±0.03 % of F.S. (at ±5 VDC range), ±0.03 % of F.S. (at ±10 VDC range)
±0.05 % of F.S. (at 4 to 20 mA DC range)



1 MΩ (for voltage input), 350 Ω (for current input)



Number of inputs


Sampling rate

2,000 times/second

Display speed

20 times/second

Display power

7-segment 3-colour LED (character height: 15.24 mm)

Over-range alarm

FFFF is displayed

Control input

NPN open-collector or non-voltage contact signal

Control input

Timing input

Hold reset input

Auto-zero input

External setting input


Setting method

4 steps x 8 programmable setups (selectable)


5 x NPN (HH, HI, GO, LO, LL): 100 mA max. (40 V max.)

Response time

1 ms (when average number 1)*1

OFF-delay time

60 ms (ON/OFF selectable)

Analogue output voltage

Output voltage

±10 VDC


100 Ω

Response time

1 ms (when average number 1)*2


Data output and control input through RS-232C

Major functions

MDL, digital fi lter, auto-zero, offset, input, data processing (10 modes),
tolerance limit storage (up to 8 sets), decimal point shift, error message display, etc.


Power voltage

24 VDC ±10 %, Ripple (P-P) 10 % or less

Current consumption

270 mA or less

Environmental resistance

Ambient temperature

0 to +50 °C

Relative humidity

35 to 85 % RH (No condensation)

Vibration resistance

10 to 55 Hz, Double amplitude 1.5 mm, 2 hours in each of the X, Y, and Z directions


Approx. 700 g (excluding fi ttings)

*1 NPN output can easily be converted to PNP output by connecting the optional OP-5148 PNP output converter.
*2 Requires 1.5 ms every second during self-compensation sequence to prevent temperature fl uctuations.

Data Sheet (PDF) Other Models