Creasol DomBus12 is a compact module, 40x30x11mm, with 9 configurable inputs/outputs.
It can be connected to the Domoticz controller by a RS485 serial bus (4 wires, 2 for 12/24V power supply, and 2 for data at 115200bps).

As other DomBus devices, DomBus12 is designed to consume low power, be reliable, fully configurable and easy to use.

Features

• 4 configurable I/Os, each one can be set as analog/digital input, twinbutton input, counter, digital output (can be connected to external relay board within relay driver)
• 2 configurable I/Os, each one can be set as open-drain output (to be connected to external relay), analog/digital input, blind output (to be connected to external relay), LED strip dimmer
• 3 configurable I/Os, each one can be set as analog/digital inputs, counter, buzzer outputs, blind outputs (to be connected to external relay board), LED strip dimmer (to be connected to external mosfet)
• 7.5-35Vdc power supply (internally regulated by a switching mode power supply circuitry that minimize power consumption and dissipation)
• low power consumption: 0.7mA stand-by current at 12V (10mW)
• 115200 bps RS485 bus (max length: 1km)

DomBus12 Ports capabilities

Default address: 0xff12

(1): can be used as BLIND output, to open a blind/curtain, but only the previous port can be configured in Domoticz as OUT_BLIND because, when configured as OUT_BLIND, DomBus device automatically configure the next port to drive a relay in open direction.

Application notes

Using DomBus12 to control two 230V devices, using the additiona module DomRelay2  (with 2 relays)

Just connect the two open-drain outputs to the 2-relays module by any type of cable (for example a standard 4x0.22mm²).

These outputs can be configured as OUT_DIGITAL or, better, as OUT_RELAY_LP: in this case the relay power consumption will be 1/3 or less.

Connecting Eastron SDM230 to DomBus12 to measure import and export energy/power on Domoticz

Many energy meters, like Eastron SDM230, provide 2 pulse outputs to count the import and export energy, 1 pulse every Wh.

Using DomBus12, DomBus23 or DomBusTH it's very easy to read the pulses from energy meters, compute the instant power and get two devices in Domoticz that show the usage and return power, usage and return total energy and graphs. Below the instructions when SDM230 is used (but check the manual of your energy meter to connect it):

1. connect the pulse outputs to any available I/O, for example IO8 and IO9 for DomBus12, IO1 and IO2 for DomBusTH or DomBus23.  The SDM230 common terminal block should be connected to GND (0V).
2. configure Pulse1 output, on SDM230, as EXP kWh (check the manual to know how to do that); Pulse2 is pre-configured as IMP kWh (measure the energy imported from grid)
3. configure the Domoticz device connected to Pulse2: press Edit on that device, and replace in the Description field IN_DIGITAL or IN_TWINBUTTON (the default value) with IN_COUNTER,TYPENAME=kWh  and save. Please note that kWh is CASE SENSITIVE!
   Now the device will be automatically moved to the Utility panel and configured as energy meter. Edit it again, write a name (for example PowerMeter_Import), and select Usage type.
4. if produced energy should be measured, configure the Domoticz device connected to Pulse1 as before: press Edit on that device, and replace in the Description field IN_DIGITAL or IN_TWINBUTTON with IN_COUNTER,TYPENAME=kWh and save.
   Now the device will be automatically moved to the Utility panel and configured as energy meter. Edit it again, write a name (for example PowerMeter_Export), and select Return type.
5. In case of both import and export devices are created, it's needed to specify on Import device the Unit number of the Export device, and vice versa. So, select Setup -> Devices and write down the Unit number corresponding to Import (for example 98), and Export device (for example 99), then go to Utility panel, edit Import device and add to the description ,OPPOSITE=99 (Unit of the Export device) and save; edit Export device and add to the description ,OPPOSITE=98 (Unit of the Import device) and save. In this way, when a pulse is received on Import device, the power on Export device will be immediately set to 0, and vice versa, when a pulse is received on Export device, the power on Import device will be set to 0.

Domoticz needs up to 5 minutes before updating the energy counter correctly.

Connecting a water meter or gas meter to Domoticz

Water and gas meter usually have an optoinsulated output that generate a pulse every 0.NNN m³.

Connecting that output to an I/O input of DomBus12, or DomBus23 or DomBusTH, and common output to GND, it's possible to get an incremental counter in Domoticz measuring water, gas, and anything else: counter divider, meter offset and unity of measure can be specified in Domoticz.

The I/O device connected to the meter should be configured in this way: click Edit on the domoticz device, write the appropriate name (for example Water_Meter), replace the current device type (e.g. IN_DIGITAL) in the Description field with IN_COUNTER and save: the device will be moved to the Utility panel and is ready to count pulses.

Using DomBus12 module to control 2x 230V loads by using 2 buttons, 4 magnetic contact sensors and 1 PIR

The following schema shows how to use this home automation module to control some alarm sensors (PIR, to detect movements inside a room, and 4 magnetic contact sensors applied to windows, doors and blinds, to detect the open state and transition), and also command 2 loads (light and dehumidifier, for example) by using the additional DomRelay2 board (within 2 relays) placed near the loads and connected to DomBus12 by a small wire cable.

Both DomBus12 and DomRelay2 are very small modules that can fit everywhere.

The two buttons are connected together by a 4k7 resistor and connected to a single input wire: this configuration is called "twinbutton" and permits to use 2 buttons for each module input, and is normally used by double buttons with the function UP/DOWN (applied to roller shutters, for example) or ON/OFF.

DomBus12, DomBus23, DomBus31 and DomBusTH have also the possibility to send command directly to other devices of the same family (and also to itsself), with the following gains:

1. very easy configuration (don't need to configure the controller); for example it's possible to configure a button to activate a load, writing the command on the device description like shown below
2. up to 8 commands are supported for each input/sensor
3. these commands are received and managed by DomBus modules without any latency introduced by the controller
4. commands work also in the case that the controller is down

Example: module address = 1201, with 2 buttons connected to port 1 and configured as IN_TWINBUTTON, with the following functions:

Short pulse on DOWN button to get light (connected to port 6 of module 1201) ON for 120s: DCMD(Pulse)=1201.6:ON:120s

2s pulse on DOWN button to toggle the same light ON/OFF without any timer: DCMD(Pulse2)=1201.6:TOGGLE

Short pulse on UP button to swith the dehumidifier (connected to port 5 of module 1201) ON for 2 hours: DCMD(Pulse)=1201.5:ON:2h

1s pulse to switch dehumidifer OFF: DCMD(Pulse1)=1201.5:OFF

To configure the port 1 of module 1201 in this way it's sufficient to edit the port 1 device in Domoticz, and write in the description all commands above:

IN_TWINBUTTON,DCMD(Pulse)=1201.6:ON:120s,DCMD(Pulse2)=1201.6:TOGGLE,DCMD(Pulse)=1201.5:ON:2h,DCMD(Pulse1)=1201.5:OFF

Then light and dehumidifier will work even if Domoticz is offline.

MORE INFORMATION AT https://www.creasol.it/CreasolDomBus12