Time-sharing proportional control (NN-200 / 210)

✔ Compact design saves installation space. The depth is as small as 150 mm, and it can be attached to a commercially available control panel.


● Compact design saves installation space. The depth is as small as 150 mm, and it can be attached to a commercially available control panel.
● Adopting a high angle meter, it is possible to read accurately over a wide range despite its compact size.
● Proportional control is possible at the same cost as ON-OFF control by the time division proportional control function.
● By adopting a relay (AC230V 2.5A) with a large contact capacity, it is possible to operate the pump and solenoid valve directly.


Model NN-200 NN-210
control method Time division proportional control
Measurement range 0~14pH ±700mV
Indicator minimum scale 0.2pH 20mV
accuracy ±1% F・S
input Glass electrode Gold or platinum electrode electrode
Input resistance 5×1011Ω以上
Compatible temperature compensation electrode Pt100
Transmission output Non-insulated type DC4~20mA(Load resistance 0-500Ω)
Setting method Upper and lower limit electronic volume setting (set value is indicator monitor method)
Repeat time (T・I) 5~30Seconds
Proportional band (P・B) 1~3pH 100~300mV
Output contacts Upper and lower limits 1c each
Output contact capacity AC230V 2.5A(Resistive load)
Ambient temperature 0~50℃
Power supply AC100V ±10% 50/60Hz
power consumption about 5VA
mass about 2.0kg

Example of use

Continuous neutralization

The pH value of the continuously flowing raw water is adjusted to the neutral range and drained by overflow. Adjust the operating time of the grout pump to adjust the pH and inject the optimum amount of grout for the target value. If the pH value is high, the pH value may be adjusted in two steps.

Batch neutralization

If the amount to be discharged per day is fixed, the entire amount is once received in the tank, and the pH value is slowly and surely adjusted and discharged while circulating and stirring. Although it takes time to process, it can reliably process high pH values.

Carbon dioxide neutralization

Basically, it is the same idea as continuous neutralization, but when the pH value of raw water is about 8 to 11, it is a system that neutralizes using carbon dioxide gas for safer neutralization. Since high-pressure carbon dioxide injection requires finer control, it is controlled by using the NN2000 and PXR5 type PID controller together.

Redox treatment

If bacteria such as bacteria are present in the wastewater, sterilize (oxidize) with sodium hypochlorite (sterilizer), and when sterilization is completed, inject a reducing agent to offset (reduce) the sterilizing power. To do. The control is performed using an ORP (oxidation-reduction potential) meter.

Head Office

1-12-11 Tagawakita, Yodogawa-ku,Osaka

Overseas Business Department

TEL +81-6-6301-6460
FAX +81-6-6308-3022