Objective
Connecting a controller to the PC wirelessly via a RS232 port or RS485 (N2 Bus). This solution can be used, for example, to commission / perform tests on an Air Handling Unit being in front of the unit, even if the panel that contains the controllers is not near the AHU.
Benefits
- Wireless connectivity over a long range
- Freedom of movement
LM Technologies Ltd Product Used
- LM058 Bluetooth Serial Adapter
- LM048 Bluetooth Serial AdapterJohnson Controls uses a pair of LM058 or LM048 adapters as cable replacement between the PC and controller.
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| View LM058 product specs… | View LM048 product specs… |
Operation
Two LM058 devices working in pair can act as a physical RS232 cable.The devices are considered pair when they can only talk between themselves. When powered up, they will automatically connect to each other. The devices will reject connections from any other devices, except for the paired device.The setup is shown below.(fig. 1)One LM058 is connected to laptop and is powered via the USB port of the laptop and the other LM058 is connected to the controller and is powered via external power supply.
The below setup (fig. 2) shows wireless connectivity between a laptop and controller via RS485 (N2 bus)
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| fig 1 |
fig 2 |