Short note: For information regarding Daikin's units (e.g. how many cards are required, control panel etc.), please contact Daikin Technical support, as they can advise better on their products.
Mounting
The RTD-W interface can be mounted on DIN rails, or on a surface using screws of up to 5mm diameter.
The RTD-W is supplied with 4 mounting pillars that can be used to mount the interface within units with compatible mounting holes.
Please contact Daikin Technical Support for further details on mounting a RTD interface inside a Daikin indoor unit, as they as can advise you better on their products.
Power
The RTD requires a 15V to 24VDC power connection (see the power ratings, as well as WARNINGS and CAUTIONS on page 4 of attached installation instructions).
Power can be supplied from the X9A connection at the A3P PCB (location is described in the indoor unit's Service Manual). A 1m cable and connector is supplied with the RTD-W. If the power supply is taken from the X9A, limitation of options is possible (please contact Daikin Technical Support for further details on powering the RTD from a unit). A 1m cable and connector is supplied with the RTD.
An external DC power supply can be used as power source, too.
P1P2
Use the P1P2 terminal to connect the RTD-W to the unit.
Please follow this link for information about P1P2 network requirements.
The RTD-W operates in SUB P1P2 mode with a BRC21 remote controller configured as MAIN (allows access to installer mode). Operation without a wired remote controller may not be possible and will cause a Fault signal.
Please note that RTD-W acts as a remote controller. As such it sends a specific command to the indoor unit. See hydrobox instructions for number of controllers that can be connected to P1P2.
Wired remote controller
Please follow this link for information on how to configure a device to MAIN or SUB P1P2 mode.
RS485
RS485 Cables must use stranded 24awg shielded or unshielded twisted pair to Cat3, Cat4 or Cat5 specification. Use a twisted pair for connections DB,DA and an extra core for connection GND. Install RS485 cable as shown in figure 4 of the RTD-W installation instructions. For further details see page 5 of the installation instructions (RS485 Network Installation).
DIP switches
DIP switches 1 and 2 must be in OFF position. DIP switches 3 - 8 are used for setting the Modbus address (if used). If Modbus is not used then the DIP switches 3 - 8 can be left in OFF position.
Hardwired Inputs (S1 - S6)
Parameters can be controlled using the hardwired inputs (S1 - S6). The use of any of the inputs is optional, i.e. if your application doesn't require the use of hardwired inputs then they can be left open.
When using hardwired inputs Voltage is only applied to input S6. Voltage input is accurate to 0.1V, allowing the setpoint to be defined to the nearest 1°C (higher temperature resolution not possible). The inputs S1 - S6 are not reconfigurable.
When installing take note of the following:
The default Update Mode is OnChange. This is important when at least two of any of hardwired inputs, Modbus, and remote controller are used for control. An example of what the effect is:
S1 is closed, unit is off. If the end user switches the unit on with the BRC then the unit will switch on, even though S1 is still closed-circuit, because the unit On/Off status will change when any of the inputs (BRC, Modbus,S inputs) changes. In this state, to switch Off the unit with S1, S1 needs to be opened and closed again!
Please see the attached installation instructions for further details.
Modbus
The RTD-W supports the Standard RTU Modbus protocol. Please follow this link for RTD baud rate and parity settings. The RTD-W Modbus registers are listed in the installation instructions. Please have a look at our article Using Modbus with our interfaces.
The RTD-W only operates as Modbus slave. Therefore, it can have any Modbus address in the range 0 - 63.
Some readback registers require the knowledge of the indoor unit's PCB number (see page 10 of the installation instructions). As described in the RTD-W installation instructions the first two digits xx of Ixx00 correspond to the PCB number 01 to 16. The PCB number is determined by Daikin's devices and you may be able to set it with the wired remote controller (Daikin Technical Support will be able to inform you how it is set).
Availability of some parameter control functions and readback registers depends on the functions available on the attached equipment, as well as system configuration. Any fields that are not available will return a value of 32767 and Modbus commands sent to these registers will have no effect. For example configuring an Altherma system for "Room Temperature Control", in this configuration H0001 and H0002 are not visible and report 32767. The Altherma HT Control Mode would need to be changed to "Leaving Water Temperature Control" after which H0001 and H0002 will be accessible.
You can also use our free software ModTool to view all the parameters and by clicking with the right mouse button on a parameter the register's address will be shown. For further information regarding ModTool, please click here.
Relays
The relays are normally open and they close when there is a respective signal. The relays are Volt-free contacts (dry contacts) and operate as described in the RTD-W installation instructions. Please note the allowed power ratings on page 4 of the installation instructions.
Single faults cannot be masked.
Status LEDs
The RTD LEDs signal various statuses during start-up, as well as during operation. For explanation of the LED (LED 1 and LED 2) signals please see page 5 and respective figures in the Installation instructions.
Once communication over P1P2 between RTD-W and indoor unit(s) has been established LED 3 should be flashing indicating that information is being exchanged between the RTD and the indoor unit(s).
Fault Signals
A Fault is signalled by relay R2 . The exact fault code can be read either on the wired remote controller display or via Modbus (see the article RTD Fault Codes).
Testing
Testing can be performed via hardwired inputs (S1 - S6), as well as Modbus.
We recommend use of our software ModTool for testing. See the article ModTool Communication with our Products.