AKO-16526 / AKO-16526A V2 Controller: Controlling an Electronic Expansion Valve (Stepper-Type)

Introduction

The AKO-16526 / AKO-16526A V2 controller is designed to manage electronic expansion valves (EEVs). It can directly control PWM-type EEVs or, when used with an external driver, Stepper-type valves. The controller optimizes evaporator efficiency by adjusting the EEV opening based on evaporator outlet pressure and temperature to maintain a specific superheating value, configurable via the 'Sh' parameter.

Wiring Diagram

The wiring diagram illustrates the connections for the AKO-16526 / AKO-16526A V2 controller. Key components and connections include:

• Controller: AKO-16526 / AKO-16526A V2.
• EEV Driver: Connects to the controller's analogue output (e.g., 4-20 mA or 0-10 V) and controls the Electronic Expansion Valve (EEV).
• Sensors:
  • Evaporator sensor (connected to S1).
  • Low pressure sensor (connected to D1/S2).
  • Superheating sensor (connected to D2/S4, function depends on parameter I20).
  • Cold room sensor (connected to S5).
  • Suction pressure sensor (connected to S6).
• Outputs:
  • AUX 3 (ON/OFF relay).
  • AN OUT (Analogue Output, configurable for 4-20 mA or 0-10 V).
  • D1, D2/S2, S5, S6 terminals for sensors.
  • AUX 1 (ON/OFF relay, configurable for DEF, FAN, COOL).
• Power Input: 100-240 V~ 50/60 Hz.
• System Components: Liquid Container, Compressor, Condenser, Evaporator, Liquid Solenoid, Evaporator Fans, Defrost Resistors/Solenoide.

The function of the D2/S4 input is determined by parameter I20. The function of the AUX 2 relay is determined by parameter o10.

For detailed information, refer to the user manual available at: https://help.ako.com/assets/uploads/351652662.pdf

Initial Configuration

Pre-Configuration Steps

Before starting the initial configuration, gather the following installation details:

• Defrost Method: Note the method used (Electrical resistors, air via evaporator fans, hot gas valve, or cycle reversal).
• Analogue Outputs: Specify the configuration for the analogue output (e.g., 4-20 mA or 0-10 V) based on the external controller's specifications.
• SET POINT (temperature): Record the desired target temperature.
• Type of Gas: Identify the refrigerant gas used in the system.
• Pressure Sensor Type: Note the type of evaporator pressure sensor (e.g., 4-20 mA, 0-5 V, 0-10 V) and its minimum/maximum values (in bar or Psi).
• Superheating SET POINT: Enter the desired optimum superheating value.

Assistant Mode

Upon first power-up, the controller enters ASSISTANT mode, indicated by the "[initialization indicator] ini" flashing. Use the ▲ and ▼ buttons to adjust values and the SET button to confirm and proceed to the next step.

Step 1: Installation Type

Select the most appropriate installation type from the table below based on the system configuration and press SET.

Note: If installation types 2, 5, or 7 are chosen, parameter I11 must be configured according to the pressure switch type used.

Step 2: Refrigerant Gas Selection

Define the refrigerant gas type by selecting the corresponding code. Examples include:

• u02=0: R404A
• u02=1: R134A
• u02=4: R410A
• u02=7: R744
• u02=9: R290
• u02=10: R32
• u02=16: 1234yf
• u02=22: R452A
• u02=23: R452B
• u02=24: R454A

A comprehensive list of supported refrigerant gases and their codes is available in the full documentation.

Step 3 & 4: Pressure Sensor Values

Define the minimum (I62) and maximum (I63) values for the pressure sensor, corresponding to the sensor's output signal (e.g., 4 mA, 0 V, 10 V). These steps are only visible if `u02=7` (R744).

Step 5: Temperature Set Point

Enter the desired temperature set point.

Step 6: Default Parameters

Choose whether to set all other parameters to their default values (dFP=1) or not (dFP=0). This option appears only if the wizard has been run previously.

Once configuration is complete, the device will start regulating the temperature.

Wizard Reactivation

The configuration wizard does not reactivate automatically. To access it again, put the unit into standby mode (hold the [standby indicator] button for 3 seconds), wait for regulation to halt (indicated by a permanent [standby indicator] light), and then press the ▲, ▼, and SET buttons in sequence.

Additional Configuration

For advanced settings, access the extended programming menu by holding the SET button for 6 seconds.

• Set parameter u00 to 2 to enable the Stepper-type electronic expansion valve control.
• Configure parameter o30 (Analogue Output) according to the driver's specifications for the electronic expansion valve connection (e.g., o30=0 for 4-20 mA, o30=1 for 0-10 V).

Manufacturer Information

AKO ELECTROMECÁNICA, S.A.L.
Avda. Roquetes, 30-38
08812 Sant Pere de Ribes.
Barcelona, Spain
www.ako.com

AKO ELECTROMECÁNICA, S.A.L. reserves the right to supply materials slightly different to those described in its data sheets. Updated information is available on the website.