pH/ORP-3500 series is a kind of popular and cost-effective online pH and ORP
controller , with plug-in pH/ORP-1220 sensor, which have good measurement
accuracy, anti-interference,easy to install and operation features.
􀂾 White backlight LCD screen,several operations, easy for operation
􀂾 Be compatible for six kinds of buffer solution(10.00,9.18,7.00,6.86,4.00,4.01)
which suitable for international standard.
􀂾 Selectable temperature sensor which reduce the replacement cost.
􀂾 Manual calibration is easy for on-site calibration.
􀂾 EMC enhancement type could run smoothly under kinds of industry
􀂾 (4~20)mA output support instrument/transmitter modes and satisfy all
(4~20)mA receiving unit.
􀂾 Double relay high/low and delay control function could fulfill pH or ORP
interval control and adjustment.
􀂾 Several power supply to be selection according to the different models.Input
AC/DC power, no polarity connection.

1.1 Working Principle
The weak voltage change is generated when H+ affected the inserted sensor, the
changeable value will transmit to the instrument. After converting and calculating the
generated pH/ORP signal, the instrument will show the values on the screen.

This series instruments are widely used for online pH/ORP monitoring in
environment protection water treatment, pure water treatment, industrial process and
so on.

1.3 Classification


  1. Put the instrument in dry environment and the water-drop or moisture will
    cause the damage or measurement error;
  2. Pay more attention on the power supply before wiring connection.

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