HANNA Instruments Logo
SKU HI504112-1 Category

Digital pH/ORP Controller with Tele-Control™ and Sensor Check™ - HI504-1

All prices are VAT excluded and without shipping costs, unless otherwise stated.

The HI504 Series offers elevated performance capabilities, rugged design and exploit an intelligent and advantageous use of tele-control technology. The different models of the HI504 series are designed to fit your individual needs, able to satisfy whatever application of monitoring and regulation you might require. Couple with Hanna industrial pH and ORP probes to meet all your industrial monitoring needs.

  • Fail Safe Alarm System protects against problems caused by power supply failure or signal interruption
  • Sensor Check™ pH/ORP alerts you if there is something wrong with the electrode
  • Logging of the last 100 events

Buy now with confidence

Request a quotation

3 in stock

Request quotation

Request a quotation

This product cannot be purchased online. Fill in the form to get a quotation, thank you.

HI504 is a PID, PI, digital pH/ORP controller with one or two set points. The measurement configuration settings and control of pH and ORP are saved separately and permits users to switch between pH and ORP without losing settings. The pH channel can be calibrated in 2 calibration points. The instrument has a full auto diagnostic procedure. Sensor Check™ is also available for pH and ORP probes.

The temperature is continuously monitored using a temperature sensor (Pt100 or Pt1000 type) with automatic temperature compensation of pH.

One or two analog controller outputs (0-20 or 4-20 mA) can be configured for pH/ORP recording or controlling (only for models with PID), and relays can be used to control the process or be connected with alarm status.

Controller status is visable with LED’s on the front panel and on the LCD display.

Fail Safe Alarm System

Hanna’s exclusive Fail Safe Alarm System protects against problems caused by power supply failure or signal interruption, which are typical risks in industrial environments. An alarm condition is indicated by a red LED, located directly on the front panel of the controller.

Programmable Cleaning Cycles

Heavy-duty applications often require almost continuous probe maintenance. Elements such as suspended solids, fat, oils, pigments and microorganisms can quickly deposit and soil the glass bulb of a pH probe, the sensor of an ORP probe or the reference junction. Programmable cleaning cycles allow for scheduled maintanence to keep the probe functioning optimally.

Analog Output: Data Logging or PID Dosage Control

Models are available with one or two analog outputs. These outputs can be connected to a recorder for the catalogging of process data (pH/mV and temperature), or can be used for controlling dosing systems (pumps or electrovalves) using PID control.

Sensor Check™ pH/ORP

Sensor Check™ performs self-diagnostic and troubleshooting functions by continuously verifying the electrode status based on impedance movement of the glass and reference measurement.

Programmable Hold System

The hold function allows the user to stop the regulating action of the controller for programmable time periods. It is possible to activate the hold periods in correspondence to programmed operations, such as plant maintenance and cleaning procedures.

Logging Capabilites 

The controller logging feature can save up to 6000 samples pH/Check°C or ORP and last 100 error, con guration, calibration and cleaning events. This information is accessible from a PC through RS485 and HI92500 software. 




2.00 to 16.00 pH


0.01 % pH


±0.02 pH



2000 to 2000 mV


1 mV

Accuracy (@20°C/68°F)

±2 mV


Temperature Range

-30 to 130.0 ºC

Temperature Resolution 

0.1 ºC above -10 ºC; 1 ºC below

 Accuracy (@20°C/68°F)

±0.5 ºC (-9.9 to 130.0 ºC); ±1 ºC (-30 to -10 ºC)

Typical EMC Deviation

±0.2 pH; ±10 mV; ±0.5 ºC

Digital Input

Digital Input for the pH/ORP/°C Transmitter: RS485 Other Digital Insulated Inputs: 2 digital insulated inputs: 1 for hold and 1 for the advanced cleaning, ON state: 5 to 24 VDCD

Digital ouput

A digital insulated contact closed upon hold mode

Temperature Compensation

Automatic or manual from -30 to 130 ºC

Analog Output

• 2 independent outputs
• 0 – 22 mA (configuring as 0-20 mA or 4-20 mA)

Data Logging

6000 pH/°C or ORP samples


Temperature Probe: With 3-wire or 2-wire Pt100/Pt1000 sensor (with automatic recognition and damage test)

Power Supply

24 Vdc/ac
230 Vac, 115 Vac or 100 Vac ±10%; 50/60 Hz

Power Consumption 

10 VA

Over Current Protection

8 MHz

Relays 1,2

Electromechanical relay SPDT contact outputs,
5A-250 VAC, 5A – 30 VDC (resistive load)
Fuse protected: 5A, 250V Quick Blow Fuse

Max. Oscillation Frequency

10 VA

Alarm Relay

Electromechanical Relay SPDT contact output,
5A – 250 VAC, 5A – 30 VDC (resistive load)
Fuse protected: 5A, 250V Quick Blow Fuse


0 to 50 ºC; max 85% RH non-condensing


Enclosure: single case ½ DIN
Casing:IP20 (housing); IP54 (front panel)


approximately 1.6 kg (3.5 lb.)

Ordering information

BL981411-0 (12 VDC) and BL981411-1 (115V) are supplied with mounting brackets, transparent cover, and instruction manual.

Additional Informations

Additional information




, ,

Quotation request

Note: fields marked with * are mandatory.

Can't you find what you need?

We have over 3.000 products in our catalogue. Register now and download the catalogue or contact us and see if we can help you.


Login to your account or create one right now to access to our exclusive content.