TECHMO 7785 Series Sensing Eye785 Amplifier-Integrated Electrical Resistivity Sensor

Manufacturer : TECHNO MORIOKA
Model: 7785 series

Amplifier-integrated electrical resistivity sensor with serial communication and alarm output functions.

Mounting piping G1/2; confirmation; Amplifier and sensor integrated; dc power supply; Serial communication; No water quality information provided; Analog output; Mounting diameter R1/2

This is an ultra-compact amplifier-integrated electrical resistivity sensor (resistivity sensor).
The screw-in portion is small (R1/2, G1/2), allowing for space-saving installation.
The A1XX and A3XX series feature analog output (4-20mA), while the A2XX and A4XX series have serial communication and alarm output,
enabling water quality measurement and management in combination with control and display devices such as PLCs.
It supports high water temperatures up to 90°C, making it suitable for use in medical and food processing equipment requiring hot water disinfection.
The electrode structure (cylindrical electrode) is less susceptible to the effects of metal piping, allowing for direct screw-in into metal conduits.

Product-compatible water quality

Product usage

Product Specifications

Model	7785-A121	7785-A221	7785-A321	7785-A421
Measurement range	1–20 MΩ·cm
Product size	W35 × H90.5 × D36.3
accuracy	Measurement accuracy: ±3.0% FS (at 25°C water temperature) Repeatability: ±3.0% FS (at equivalent resistance)
Analog output	4-20mA DC (0 to FS = 4-20mA)
Transistor output	none	FET open-drain output Drive load conditions: DC24V 50mA or less	none	FET open-drain output Drive load conditions: DC24V 50mA or less
Serial communication	none	RS-485, Modbus RTU, 9600bps, 8bit, 1stopbit, Non parity	none	RS-485, Modbus RTU, 9600bps, 8bit, 1stopbit, Non parity
power supply	DC24V (2.0W or less)
Usage environment	Ambient temperature 5-60°C (if water temperature is 80°C or higher, keep it below 45°C) Ambient humidity 5-80%RH (but no condensation)
Connection port diameter	R1/2		G1/2
cable	3-core cable, 2m (24V, GND, 4-20mA)		6-core cable, 2m (24V, GND, 4-20mA, D+, D-, Tr)
others	Power supply isolation improves noise immunity. Electrode structure less susceptible to interference from metal piping, allowing direct screw-in to metal piping. Sensing eye 575 compatible and replaceable. RoHS2 compliant. 7785-A221, A421 serial communication allows simultaneous acquisition of water quality and water temperature data. The serial communication protocol uses the general-purpose Modbus protocol. Serial communication function facilitates data acquisition (water quality, water temperature) for multi-point measurements. Transistor output function simplifies water quality management.