Custom applications
For examples regarding custom Duty/Standby application, please read this article.
Q: Can I configure the inputs different their standard use? I want to use one input as heat signal, and one input as cool signal.
A: No, this is not possible.
Q: I need to bypass an RTD-10 unit to allow Daikin units to run normally on their own controls. Is there a way to disable the RTD-10 and leave it in situ without having to disconnect any wiring?
A: If you only want to unlock the remote controller you can do that either by changing the S6 input value, or if you are using Modbus then by changing the value of the Update Modbus Registers, as described in the RTD-NET datasheet. Or you can simply unplug the P1P2 connection of the RTD-10 and keep only the remote controller connected to the indoor unit. If you unplug the P1P2 connection of the RTD-10 then you will not be able to read any status data from the unit (Modbus, relays), of course.
Q: I want to control the RTD-10 based on Outdoor Temperature.
A: This is not directly possible with the RTD-10. You will have to implement this by means of an external digital controller which receives the Outdoor Temperature and controls the RTD-10 via Modbus or analogue inputs.
Q: I have two indoor units each controlled by a RTD-10 interface. I want the second unit only to switch on when the first unit is Off, loses power, or has a fault.
A: You will need to cascade the RTD-10 interfaces by connecting the S5 input of the second interface to the Relay outputs of the first interface. To run the second unit on power loss of the first unit it may be better to use an additional relay at the power supply of the main RTD-10 which closes when the power is lost. This relay's output will also need to be connected to the second RTD-10's input S5.
Q: I want the RTD-10 relay to close when the indoor unit's Return Air temperature is in the range of -1 to -3 DegC.
A: Probably the closest to your requirements is to configure any of the RTD-10 relays to 'Unit has Thermostat Demand for Heating' (see this article). However, it is not possible to add a further requirement that the relay only closes when the temperature is in the range of -1 to -3 Degrees Celsius. If you place in series to the RTD-10's relay a relay which closes within your specified temperature range (-1 to -3 DegC) then your requirement (as described above - see point 2) would be satisfied. Optionally, ff you are using Modbus then you could control the relays from your modbus master.
Inputs
Q: What is the maximum Voltage I can apply on input S5?
A: The maxmimum input voltage is 10 VDC. Please note that the maximum Voltages applicable are listed in the RTD-10 installation instructions on page 6 (section 'Specifications'), as well as in the respective operation mode section.
Q: With the the RTD-10 interface (Standard operation mode) having the facility for both “hard wired” control and Modbus control, which takes precedence if both were used?
A: For RTD-10 in Standard Resistance or Voltage mode:
Each input control parameter on S1 to S5 can be locked or unlocked by different input values on S6.
If an input control parameter is Locked then the value on the associated input is continuously written to the AC unit, the Remote Controller is locked, and any Modbus values will be overwritten. If an input control parameter is NOT Locked, then updates from input S1 to S5 only occur on change, where a change is typically more than 0.25V or 250 ohms. The value in the corresponding Modbus register will be changed by the input, but if no change occurs on the input then the Modbus values can be written to, as can the control button on the Wired Remote Controller.
Q: When powering On the system I want all indoor units to start with the parameters set by hardwired inputs S1-S6 (resistance mode). Nevertheless, I want to be able to control the indoor unit with Modbus and Remote Controller.
A: If you want the indoor unit to load the S1-S5 inputs first upon switching (or powering) the indoor unit ON, then you have to use S6 to lock the wired remote controller (RemCon) buttons which correspond to the respective S1-S5 inputs.
Once the parameters have been loaded you should unlock the RemCon buttons (with switch on S6). This will allow the user to use Modbus and RemCon to change the parameters which correspond to hardwired inputs S1-S5.
Please note that If you set the RTD-10 to P1P2 MAIN then the connected indoor units will be switched ON when the indoor unit is powered ON (e.g. after a power failure). If you don't want that then you have to set the RemCon as P1P2 MAIN.
Q: What does the input S6 lock?
A: If you lock with S6 then wired remote controller and Modbus are locked: Only values of the hardwired inputs S1-S5 will be used (if not connected then default values will be set). If you want to control only with S1-S5 and Modbus (i.e. only lock the RemCon) then use the Update Holding Registers H0010 - H0015 and set the required register to Central (in ModTool: 'Locked').
Fanspeed
Q: Does the RTD-10 support Auto Fanspeed?
A: No.
Q: If I set the the Fanspeed to High2 or HIghHigh, but the Indoor Unit doesn't support this speed. Which speed will then be applied to the fan?
A: In this case the Fanspeed will be High.
Q: If I set the Mode to Auto will then the Fanspeed also be Auto?
A: Setting mode to Auto does not influence the fanspeed. However, there may be operation conditions when the Daikin indoor unit changes the fanspeed. We recommend you inquire at Daikin Technical Support in this regard.
Q: Will the Fan run even I switch the Indoor Unit OFF?
A: No.
Q: For the R1 relay status, will the relay close if either the fan is on or the cool/heat is running, or will it ignore the fan status and only close if the system is actively heating or cooling?
A: The relay will close when the indoor unit is ON. This is the case when the unit is any of Heating/Cooling/Fan/Dry modes.
Louvre
Q: Is 0 degrees (default) on the Louvre control (S4) fully closed or open?
A: Flap position = 0 degress means that the flaps are in horizontal position. We recommend you inquire at Daikin which air discharge angles are actually possible for the indoor units you are using.
Remote Controller Temperature
Q: Can I read the Remote Controller Temperature?
A: You can change the Field Settings of the Indoor Unit such that the Remote Controller sensor is used instead of RA sensor.
Mode Readback
Q: If we set the mode to Auto, is there a way to see if the system is heating or cooling, not just “on”? Please let us know if there is a modbus register we can query, or if there is another output we can read.
A: You can read the unit operation via Modbus Input registers In0030 and In0*30.
Another option is reconfiguring the relays (see this article) such that they signal either
a) Unit is ON and in COOL, AUTO:COOL, or DRY, or
b) UNIT is ON and in HEAT, AUTO: HEAT.
If this option is what you require, please let us know.
Please note that dependent on the indoor unit type the Thermo On status read may only show the demand, but not the actual heating/cooling status.
Setback function
Q: Does the RTD-10 offer a setback function like the RTD-HO?
A: No.
Auto mode
Q: Will the indoor unit ever go into Dry mode if we set S3 to Auto?
A: In Auto mode the indoor unit will not switch to Dry operation. We recommend contacting Daikin for information if any operation conditions do start the Dry mode.
Q: If S5 is ON, and S3 is Cool, will the indoor unit start cooling, even if the setpoint is below the current room temperature?
A: For this request please contact Daikin Technical Support, as they can inform you best how the system behaves when the indoor unit is set to Cooling mode, but no Cooling is required.
Q: Does the RTD-10 support Auto Fanspeed?
A: No.
Faults
Q: Where is fault signal generated which causes the relay R2 to close?
A: The fault signals are generated by the indoor unit.
Temperatur Sensor
Q: Is the RTD-10 equipped with its own temperature sensor?
A: The RTD-10 is not equipped with its own temperature sensor. You can only have the RTD-10 control with reference to unit or BRC sensor by changing the field setting in the BRC.
In Duty Standby you can connect an external thermostat to provide alarm monitoring in the controlled space.
Deadband
Q: Can we connect a Thermostat to the RTD-10 such that it controls the temperature to remain at 23.5 DegC +- 1.5 DegC?
A: Please contact Daikin Technical Support for information on their units and changing the deadband, and the use of external thermostats.
Q: What is the deadband around the setpoint for Auto mode?
A: Please contact Daikin Technical Support for further information on the dead band and whether it can be reconfigured.