eDrive is capable of communication with devices that use the Open N2 protocol developed by Johnson Controls Incorporated.
When Open N2 devices are connected to an RS-485 serial bus eDrive can only communicate with them by tunneling N2 messages over an ethernet IP network. Request messages are sent be eDrive over the IP network to a serial server device which routes them on to the serial bus. When the Open N2 device replies to the request, the serial server routes it back to eDrive over the IP network.
Device Name
Enter a descriptive name that eDrive will use to reference this device. Spaces and punctuation characters are allowed.
Device Type
From the drop down list, select the option: Open N2.
Polling Timeout
From the drop down list, select the value (in seconds) that will determine how long eDrive will wait for responses from this device before declaring a timeout event and moving on to its next task.
The intent of the timeout period is to allow enough time for the device to fully respond to requests from eDrive, but also allow eDrive to move on to other tasks if the device is offline and not able to respond.
IP Address
Enter the IP Address of the serial server device connected to the RS-485 serial N2 bus.
Port
Enter the IP Port Number of the serial server device assigned to the RS-485 serial bus.
Target Interval
Enter the value (in seconds) that represents how often this device needs to poll all of its Point Objects. eDrive will distribute its polling activities over the Target Interval and attempt to complete the polling for all of its Point Objects within the Target Interval if possible.
Example: All selected points for this device only need to be updated once every 2 minutes. Set the Target Interval to 120 seconds.
When practical, use a longer value of Target Interval to spread out the polling activities and minimize impact on network bandwidth.
Pacing
For Open N2 device type, eDrive is capable of multi-threaded polling to improve throughput. Pacing sets the amount of time eDrive will wait before launching an additional polling thread for the same device.
If the device responds to requests quickly, before the Pacing interval is reached, no additional threads are needed.
If responses from the device take longer than the Pacing interval, eDrive will launch an additional thread to poll for point values. (see Maximum Polling Threads parameter below.)
Maximum Polling Threads
Many serial server devices utilize a TCP stack designed to handle multiple requests in a queue for sequential processing. Performance gains are possible by allowing eDrive to send point value requests on multiple threads and utilize the serial server's TCP stack.
Maximum Polling Threads value can be set from 1 to 8. A value of 1 will limit eDrive to use only a single thread and poll for all Point Objects sequentially. Higher values will allow eDrive to maximize throughput to the device if it is capable.
Device Address
The bus address of the Open N2 device on its RS-485 serial bus.
Open N2 Point Object Configuration Parameters:
Name
Enter a descriptive name that eDrive will use to reference this Point Object. Spaces and punctuation characters are allowed.
If '/' (forward slash) characters are included in the name, eDrive will create the Point Object in a hierarchical, tree structure with the '/' characters as delimiters. The tree structure will appear in the list of eDrive objects along the right hand side of the page.
Type
From the drop down list, choose the Point Object type that corresponds to the Open N2 object type.
Object ID
Enter the (integer) value of the Opent N2 object number for this point.
Note! You can assign Additional Properties to any Point Object such as Offset, scaling Multiplier, History, etc. Please refer to the Additional Point Properties section for more detail.
When Device and/or Point Object configuration is complete, select the Submit Config function to save your changes to eDrive.
