Danfoss AK-CC55

Compatibility

Compatible with EpiSensor Edge over Modbus RTU

The AK-CC55 has Modbus RTU on RS-485 built in, which a ZMB-31 reads and sends to Edge over the EpiSensor wireless network. Danfoss publishes a basic Modbus parameter list for each variant, with the parameter number, type and scale of every readout, setting and alarm.

AK-CC55 Compact (084B4081, list for software 2.1x), Single Coil and Single Coil UI (084B4082, 084B4083, lists for software 1.3x and 1.5x) and Multi Coil (084B4084, list for software 1.7x). The earlier AK-CC 550 has its own lists and is not covered. Site check: read the thermostat air temperature at register 2531 and compare it with the display. Read-only monitoring: setpoints, defrost start, the main switch and the alarm limits stay out of the templates.

Connect it with

• Modbus Interface ZMB-3X From €399 ex VAT Configure
• Gateway ZGW-20 From €899 ex VAT Configure

Specifications

For food safety the AK-CC55 can report a product temperature as well as the control air temperatures: S6 on the Single Coil, and the food temperature U72, which may be S6 or one of the air values. That makes the controller a useful second signal. A record independent of the control loop still comes from a separate probe at the warmest product position, with the controller's state and alarms beside it.^2, 9

Variants

Compact 084B4081, Single Coil 084B4082, Single Coil UI 084B4083, Multi Coil 084B4084¹

Supply

115 V or 230 V AC, 50/60 Hz, 5 VA¹

Sensors

S3, S4 and S5: Pt1000, PTC1000, NTC5K or NTC10K, all one type; S2 and S6 (Single Coil): Pt1000¹

Measuring accuracy

Pt1000 -60 to 120 °C ±0.5 K; NTC5K -40 to 80 °C ±1.0 K; Pt1000 sensor ±0.3 K at 0 °C¹

Data communication

Built-in Modbus RTU on RS-485; AK-OB55 LON module option (not Compact)¹

Modbus terminals

83 B-, 84 A+, 85 screen (Single Coil)²

Serial settings

o03 address 0 to 240; oa1 baud Auto, 9600, 19200, 38400 or 115200; oa2 parity none (2 stop bits), even or odd (1 stop bit)²

Clock backup

4 days¹

Environment

IP20, DIN-rail mounting, 0 to 55 °C, 20 to 80 % RH non-condensing¹

Interface

Setup

1. Wire the Modbus terminals

   Wire terminals 83 (B-) and 84 (A+) to the ZMB-31 with a screened twisted pair and connect the screen to 85. On a controller that replaced an AK-CC 550, check A+ and B-: the two controllers have them the opposite way round.

2. Set the address and frame

   Set a unique address in o03 (1 or higher). Leave oa2 at even parity with 1 stop bit and set the same frame in the ZMB-31 at 9600 or 19200 bit/s; the controller's automatic baud detection follows a fixed master, or fix oa1 to the same rate.

3. Read the thermostat air temperature

   Read u17: FC03, register 2531 (PNU 2532), one register, signed 16-bit, multiplier 0.1. Compare it with the display at the same moment.

4. Import the template for the variant

   Import the Compact, Single Coil or Multi Coil template. The alarm flags are numbered differently on each, so match the product code on the label. Read q39 to know what the food temperature U72 represents, and remove points the application mode (o61) does not use.

5. Add the independent probe

   For an independent food safety record, place a TES-2X probe at the warmest product position and keep it beside the S6 or food temperature in Edge. Set its alarm limits and delays from the site's HACCP plan.

Common questions

Where is the Modbus register list?

Danfoss publishes a basic Modbus parameter list for each variant: the Compact for software 2.1x, the Single Coil for 1.3x and 1.5x and the Multi Coil for 1.7x. The lists give parameter numbers (PNU); read each at the PNU minus 1. The templates on this page carry the readouts, settings and alarms that matter for monitoring.^{3, 4, 5, 6, 7}

Can the AK-CC55 record the product temperature for HACCP?

The Single Coil takes an S6 Pt1000 product sensor between the food items, with separate alarm limits and delays, and every variant reports a food temperature U72 chosen by q39. Those readings are useful in a HACCP record. Many sites still keep an independent probe at the warmest product position, so the record does not depend on the controller that is also running the case. The food business operator remains responsible for the HACCP plan.^2, 9

The alarm flags read 0 when the display shows an alarm. Why?

The alarm numbers differ by variant: the high temperature alarm is PNU 20007 on the Compact, 20011 on the Single Coil and 20012 on the Multi Coil. A template from another variant reads the wrong flag. Match the template to the product code on the label.^3, 5, 6

Can a ZMB share the bus with an AK-SM system manager?

Modbus RTU has one master on a bus. The AK-CC55 is designed to sit under a Danfoss AK-SM 720, 350, 800 or 800A system manager; where one already polls the controllers, do not add a second master to the same RS-485 bus. Read the data from the system manager's side or give the controller its own bus.²