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HI-504924-2 pH/ORP Controller

HI-504924-2 pH/ORP Controller

Hanna HI-504924-2 pH/ORP Controller

HI-504924-2 pH/ORP Controller

Use with HI-62920D pH electrode
2 year manufacturer warranty
£1,016.00 (exc. VAT) £1,219.20 (inc. VAT)

Dual setpoint, advanced cleaning, on/off and PID control, dual analogue output, 230V

HI-504924-2 pH/ORP Controller information

Hanna's extended description

Measures and controls pH across an extended pH range of -2.00 to +16.00pH and -2000 to +2000mV with a temperature range of -30 to +130 C. A comprehensive specification allows a high degree of customisation for the pH/ORP application you wish to control:

  • Can be used to control pH or ORP
  • User selectable PID, PI, proportional on/off control of pH or ORP
  • Two user selectable dosing set-points plus 1 alarm relay set-point
  • Sensor Check for real time pH or ORP electrode status monitoring
  • Accepts inputs from either a digital transmitter or direct from an electrode
  • Matching pin compatibility to eliminate ground loop effect interference
  • Logging of up to 100 system events, and up to 6000 individual readings (pH/ORP
  • Automatic probe cleaning from alarm or user request
  • Fail safe alarm system
  • Programmable cleaning cycles and hold systems

  • The HI-504 is a PID, PI, proportional or on/off controller with one of 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.

    Temperature is continuously monitored using a temperature sensor (Pt100 or Pt1000type) with automatic temperature compensation of pH.

    One or two analogue controller outputs (0-20 or 4-20mA) 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 visible with LED’s on the front panel and on the LCD display.

    The controllers logging feature can save up to 6000 samples pH/°C or ORP and last 100 error, configuration, calibration and cleaning events. This information is accessible from a PC through RS485 and HI-92500 software. The powerful HI-92500 software has graphing capabilities and can print graphs directly or can be saved as a bitmap. Data can be exported in common spreadsheet formats.

    Fail-Safe Alarm System

    HANNA exclusive Fail-safe Alarm System protects against problems caused by power supply failure or signal interruption, which are typical risks in industrial environments. The system acts both on a hardware and a software level. The alarm relay functions in a normally closed condition, and is tripped when there is a power failure if, for example, the power cable is accidentally cut. This function is very important in industrial plants where alarms are usually not activated if there is a power supply interruption, which can cause serious damage due to a loss of control of the process plant. At the software level, the fail safe function activates an alarm in case of abnormal circumstances, for example if the dosing contacts remain closed for an excessive period. The alarm condition is also signalled by a red LED, located directly on the front panel of the controller.

    Mains powered - All mains operated equipment is compatible with UK AC voltage and frequency – 230V, 50Hz.


    Specifications list


    Range -2.00 to 16.00pJ; -2000 to 2000 mV; -30 to 130.0°C
    Resolution 0.01 pH; 1mV; 0.1°C (above -10°C; 1°C (below -10°C)
    Accuracy (@25°C) ±0.02pH; ±2mV; ±0.5° (-9.9 to 130.0°C); ±1°C (-30 to -10°C)
    Input impedance 10120hm
    Digital input for the pH/ORP/°C Transmitter RS485
    Other digital insulated inputs Two digital insulated inputs; one for hold and one for the advanced cleaning; ON state: 5 to 24 VDC
    Digital insulated output a digital insulated contact closed upon hold mode
    Temperature Compensation Automatic or manual, -30 to 130°C
    Temperature probe with three-wire or two-wire Pt100/Pt1000 sensor 9 with automatic recognition and damage test)
    Power supply (depending on model) 24 VDC/AC, 115 VAC ±10%, 230VAC ±10% or 100VAC ±10%; 50/60Hz
    Power consumption 10VA
    Over current Protection 400mA 250V quick blow fuse
    Max Oscillation frequency 8MHz
    Relays 1, 2, 3, 4 Electromechanical relay SPDT contact outputs 5A-250 VAC, 5A – 30VDC (resistive load); fuse protected; 5A, 250V quick blow fuse
    Alarm Relay Electromechanical relay SPDT contact output, 5A – 250VAC, 5A – 30 VDC (resistive load) fuse protected; 5A, 250V quick blow fuse
    Analogue output Two independent outputs, 0 – 22mA (configuring as 0-20mA or 4-20mA)
    Analogue Output resolution 0.1% f.s.
    Analogue Output Accuracy ±2% f.s
    Data logging 6000 pH/°C or ORP Samples
    Environment 0 to 50° C ; RH max 85% non-condensing
    Casing IP20 (housing); IP54 (front panel)
    Weight 1.6kg (3.5lb)
    Ordering information: HI-504222-2 Dual setpoint, on/off and PID control, single analogue output, 230V
    HI-504224-2 Dual setpoint, on/off and PID control, dual analogue output, 230V
    HI-504924-2 Dual setpoint, advanced cleaning, on/off and PID control, dual analogue output, 230V
    HI-Probe HI-7610 Stainless Steel Pt100 probe with front and back half-inch NPT thread and 5m (16.4 feet) cable

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