Mounting
The RTD interface can be mounted on DIN rails, or on a surface using screws of up to 5mm diameter.
The RTD-HO 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 VRV indoor unit PCB X18A or X35A connection, a Skyair indoor unit PCB X35A connection or VAM PCB X11A connection (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
Please follow this link for information about P1P2 network requirements.
Up to 16 indoor units can be wired via P1P2 to the one RTD-HO interface. In this case, all these indoor units will be controlled as a group and will receive the same command from the RTD-HO. The indoor units within the group cannot be controlled individually!
Please note that RTD-HO acts as a remote controller. As such it sends a specific command to the indoor unit. If you require information on how the indoor unit works when a specific command is recieved (e.g. when in Cooling mode and Return Air temperature is below requested setpoint) then please contact Daikin Technical Support.
Wired remote controller
The RTD-HO can operate without an additional wired remote controller (therefore it is optional).
- With respect to compatibility of wired remote controllers to our RTD interfaces, please read this article.
The RTD-HO can operate as both MAIN or SUB P1P2 device. For specific sets of data the RTD-HO needs to be set as MAIN P1P2 device (see attached installation instructions and readback data).
Please follow this link for information on how to configure a device to MAIN or SUB P1P2 mode.
Infrared remote controller
When using infrared remote controllers the BRC infra-red receivers must be configured to operate in SUB (S) 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 8 of the RTD-HO installation instructions. For further information see the article RS485 network requirements.
DIP switches
Several functionalities can be set using the DIP Switches. See the RTD-HO installation instructions for details on DIP switch settings and respective functions.
Hardwired Inputs (S1 - S6)
The wire from the room key card has to be connected into S1.
S2 and S4 can be used when DIP switch 2 is ON. S2 and S4 are used to determine the operation of the indoor unit with respect to window open/closed state of (a) window contact(s).
For details please see the RTD-HO installation instructions.
Modbus
The RTD-HO supports the Standard RTU Modbus protocol. Please follow this link for RTD baud rate and parity settings. The RTD-HO only operates as Modbus slave.
The Modbus address range 0 to 31 is set using Dip switches 4 - 8 (see figure 9 in the RTD-HO installation instructions).
It only possible to monitor (read data) the unit via Modbus, i.e you cannot control a unit with Modbus. Group readback data registers are listed in the RTD-HO installation instructions.
Further details of Modbus register functionality and fault and temperature formating can be found in the RTD-NET Installation Instructions (attached to the article How to install a RTD-NET interface). See also the article Using Modbus with our interfaces.
Relays
The relays are Volt-free contacts (dry contacts) and operate as described in the RTD-HO installation instructions. Please note the allowed power ratings listed on page 5 of the RTD-HO installation instructions.
The relays' default status is normally open and they close when there is respective signal. Hence, when the indoor unit is ON relay R1 closes (even when only the Fan is operating). Note that the unit is not necessarily ON when the room is OCCUPIED.
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 6 and respective figures in the Installation instructions.
Once communication over P1P2 between RTD-HO 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 (unless otherwise configured). 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, as well as Modbus. It can be tested without connecting an indoor unit.
Testing via Modbus can also be performed with out free software ModTool: ModTool Communication with our Products.
Note that if the RTD is not connected to any indoor unit then the parameters will be reset to default. When connected to an indoor unit then the values you have set will be stored.