ZigBee Summary Of Operation

ZigBee Wireless Data Links
Summary of Operation

Overview of ZigBee System

The Z-2400 wireless series integrate ZigBee� technology to form a convenient mesh wireless network between modules. This technique allows the short range of an individual module to be expanded and multiplied, covering a much larger area.

When the mesh network discovers a new Z-2400 module, it will automatically incorporate it into the current network. Mesh networking is also designed for good redundancy.

The Z-2400 wireless series includes three models :

Z-2400-RB : Z-2400-RB modules are configurable either as Base or Remote devices, by a single DIP switch.

Base Z-2400-RB configured as a Base module, is the master of the wireless network connected to it. This module connects to the computer via RS485/422/232 and automatically keeps track of all other modules and manages the wireless network.

Remote Z-2400-RB configured as a Remote module, forms part of the mesh wireless network, plus allows connection of the Intech Micro family of field stations via RS485/422/232.

Z-2400-SLEEPER. Z-2400-SLEEPER is battery powered for those applications where monitoring of mobile equipment is required. The Sleeper module includes two universal inputs. A plug pack power supply can be added for permanent monitoring.

Z-2400-TCP. Z-2400-TCP is a Base module and is the master of the wireless network connected to it. This module connects to the computer network via TCP, and automatically keeps track of all other modules and manages the wireless network.

Additional Notes on each device

Base (Z-2400-RB, Z-2400-TCP)

There is only one base per ZigBee network. Additional bases are supported by using Mesh ID (advanced users only)
Devices set to different Mesh IDs cannot talk to each other. If two bases with the same mesh ID are located with signal range, the remotes/sleepers will not be able to determine which one to connect to. For further information on Mesh ID, see ZigBee Mesh ID.
Use only one serial Z-2400-RB on one data loop. For additional devices, use Z-2400-TCP.
The base must have a unique id on the data loop as set by its address DIP switch A (1-32).
The base maintains node lists of connected remotes and sleepers. When a device is found, it is added to the node list. When the device stops updating, a timeout interval is engaged and it is then removed from the node list.
Because of the significant handshaking required for MicroScan to interact with a station attached to a remote, it is not recommended to share a ethernet base between two MicroScans.
If the base is replaced with a new base, all Z-2400 devices should be reset to allow them to find the new base (likewise when experimenting with different bases/mesh ids within a small area).

Remote (Z-2400-RB)

A remote can be used to expand the network range by redirecting signals to other remotes and/or sleepers.
When remotes are used, DIP SWB 5 must be turned ON, on the base.
If the power is lost to a remote, other remotes/sleepers that are using this remote as a router may lose connection for a period of time until the mesh can reform. It is not possible to know that a remote is performing this router function, thus on a network with remotes all remotes should be powered up all the time.
The minimum system is 1 x base and 1 x remote.
Link Quality and Signal strength can be graphed to display connection quality to the remote.
The remote must have a unique id on the ZigBee mesh as set by its address DIP switch A (1-32), this can be set to the same address as a station attached to the remote.
When a remote connects to stations via RS422, note that the TX and RX wires must be swapped from the remote to the station.
Find Stations of the stations attached to the remote is supported via Program Station Setup Base.
Stations on a remote are accessed by a slower update rate to allow other wired stations to be accessed more quickly. (The page update rate is forced to Medium scan rate).

Sleeper (Z-2400-Sleeper)

A Sleeper is an endpoint on the network and cannot route signals to other sleepers/remotes.
When sleepers are used on a network with remotes, DIP SWB 5 must be ON on the base. At least one remote should be powered up all the time for the sleepers to connect to.
When sleepers only are used on a network, DIP SWB 5 must be OFF on the base.
Sleepers wakeup at the selected interval, take an input reading and send that to the base. Input changes that happen during the sleep interval are ignored. The base cannot force the sleeper to wakeup and send a new value through.
The network status LEDs on the sleeper are only operational at the time of sleeper initial powerup.
Setup of sleeper inputs is by XU-USB and XU Setup program.
The minimum system is 1 x base and 1 x sleeper.
Link Quality and Signal strength can be graphed to display connection quality to the sleeper.
Each Sleeper must have a unique id as set by its address DIP switch A (1-32).
Sleepers can be powered by battery (DIP SW B, 8 ON) or dc plug pack connected to power terminal block.
The sleeper's fastest update rate is 1 minute.

Operational Summary

While the base maintains the ZigBee network, the MicroScan driver manages the comms of the overall system.
Base stats are read from the base on the minute and reported to the ZigBee Status window 5 seconds later.

Communications to Remotes

When the data is needed for the station, the driver connects to the remote via the base, and then issues the read for the station attached to the remote. It takes approx 400 mSec for the complete round trip for station request and replied data to be returned. If the remote cannot be found, a timeout interval is applied to all stations that are attached to the remote, and they will then be retried when that interval expires. If one station on a remote does not respond, only that station will be marked for retry. Once a station is connected, further requests to the same station will leave the base to remote channel open. If a new station on a remote is required, the new remote will be dialed. If a local station is required, the base will be set to idle mode.

Limits on speed

When a line is attached to a station on a remote, the page scan rate of the remote is set to the medium scan rate (normally default at 15 seconds).

Error Replies

Connection Good	Current Data from station
Recent Lost connection	Last Data value from station
Permanent Lost connection	Error 1

Communications to Sleeper

The sleeper wakes up at the set interval and sends its values to the base and then returns to sleep. It is these values that the MicroScan reads from the base.
Data readings are taken from the base at 10 seconds prior to the minute to allow readings to be up to date before the next graph save on the minute (note readings may be up to 1 minute behind depending on when the sleeper update happened). Detailed information from the sleeper is displayed in the ZigBee status window: Sleeper interval, Input ranges, Input Readings, Battery Reading, Battery log, time of last reading update and connection history.

Error Replies

Connection Good	Current Data from sleeper inputs
Recent Lost connection	Last Data value from sleeper inputs
Permanent Lost connection	Error 9

Adding ZigBee Units to MicroScan

Step 1 - adding base

Add the base to MicroScan, use the Add Station Wizard.

Step 2 - adding a remote and station

a) Existing station, use the Configure Pages and Lines, Assign Remote button.
b) New station, use Add New Station Wizard

Step 3 - adding a sleeper

Sleepers are added automatically to the base, all that is needed is to attach a line or tag to the Sleeper Input 1 and Input 2 points on the base station map.