Building Automation Knowledge Base

Issue BACnet MS/TP Bus Communication Troubleshooting Checklist Product Line TAC IA Series Environment I/A Series BACnet controllers (MNB-70, MNB-V1, MNB-V2, MNB-300, MNB-1000) on an MS/TP bus. Cause BACnet MS/TP Bus Communication Troubleshooting Checklist Resolution This checklist provides several settings/configurations to review when faced with a communication problem at the controller level. The content was compiled from different resources, summarized, and laid out in an easy-to-use manner so as to provide a quick-reference document. Power Each controller requires 24 VAC from a Class 2 transformer. See the Installation Instructions for each controller, and the MicroNet BACnet Wiring, Networking, and Best Practices Guide, F-27360-7, Chapter 1, “Power Supply Wiring”. Read-Only Flag Use the WorkPlace Tech Commissioning Tool (WPTCT) to check “Device Properties” of the controller. If the status is “Operational, Read-Only”, the input voltage to the controller may be too low. See the MicroNet BACnet Wiring, Networking, and Best Practices Guide, F-27360-7, Chapter 1, “Power Supply Wiring”. Due to the short duration of the low-voltage condition required to set the flag, it is unlikely that you will see it when measuring the input voltage with a digital meter, so check the “Device Properties”, and correct the problem as noted on page 28 of the guide, (reduce transformer loading, reduce wire length between transformer and controller, and /or use wire with higher current rating). Diagnostic LEDs The MNB controllers have onboard diagnostic LEDs that are useful in troubleshooting. See the MicroNet BACnet Wiring, Networking, and Best Practices Guide, F-27360-7, Chapter 3, “Communications Hardware Checkout”, Table: “LED Indications”, for a detailed description of the behavior of the LEDs and their diagnostic uses. Topology It is very helpful to draw the topology of the bus when you start troubleshooting. If there are no repeaters on the bus, the topology must be a daisy-chain, with no tees or stars. MS/TP network wiring to MN-Sx sensors must be run to the sensor, then to the next controller on the bus, in a daisy-chain; no tees or spurs are allowed. Maximum length of a wire segment is 4000 feet. See the MicroNet BACnet Wiring, Networking, and Best Practices Guide, F-27360-7, Chapter 1, “MicroNet MS/TP Network Wiring”, for details on Communications wiring. Repeaters B-LINK-AC-S, Andover Controls MS/TP Repeater B-LINK-AC-F-S, Andover Controls MS/TP Repeater Fiber See the MicroNet BACnet Smoke Control Systems Manual, F-27419, for details on the use of these wire and fiber repeaters with MNB controllers. See F-27419, Chapter 5, “Approved MS/TP Repeaters”, including the wiring example. Maximum Number of Devices The maximum number of MNB controllers depends on the cable used, and the Baud Rate. See the MicroNet BACnet Wiring, Networking, and Best Practices Guide, F-27360-7,Chapter 1, Table, “Approved Cable Types”. The MNB controllers are quarter-load devices, so a maximum of 128 or less are allowed on an MS/TP trunk, depending on the cable used. Addressing Avoid duplicate addresses. See the MicroNet BACnet Wiring, Networking, and Best Practices Guide, F-27360-7, Chapter 1, “Required Configuration”, CAUTION: “Duplicate addresses on an MS/TP network trunk will result in erratic behavior, lost tokens, and disrupted communication. There is no software tool that will identify duplicate addresses on an MS/TP network trunk. Typically, if two controllers are set to the same address, one of the controllers will appear to be missing from the list, and the address shared by the two controllers will intermittently come and go from the list.” Biasing As a requirement of EIA-485 (formerly RS-485) bus topology, an MS/TP network must have a minimum of one set, and a maximum of two sets, of bias resistors in place. The MNB-300, MNB-1000, UNC-520, and ENC-520 have jumpers to enable or disable the bias resistors. See bulletin TB06-09, “RS-485 Bias Resistors and the UNC-520-2 / ENC-520-2”, page 3, for a photo of the bias jumpers on a UNC-520-2. Terminators A 120-Ohm End-of -Line (EOL) resistor is required across the “MS/TP +” and “MS/TP -” terminals at each controller at the end of a wire segment. The MNB-1000 and MNB-300 are equipped with a jumper-selectable end-of-line (EOL) termination resistor. The default position for the EOL jumper is “EOL termination not present.” See the MicroNet BACnet Smoke Control Systems Manual, F-27419, Chapter 5, “Approved MS/TP Repeaters”, Figure titled “UL 864 Listed MS/TP Repeater and Isolation”, Note 4, for an important exception, requiring external EOL for the MNB-300 and MNB-1000, when used on a bus with an approved repeater. If a UNC-520-2, ENC-520, MNB-V1 or MNB-V2 is installed at the end of the trunk, install a discrete 120 Ohm EOL resistor, part number EMSC-546, or equivalent. Cable Use of the proper cable is critical to the communications performance of the networked controllers. See the MicroNet BACnet Wiring, Networking, and Best Practices Guide, F-27360-7,Chapter 1, Table, “Approved Cable Types” for a list of recommended cable types. As shown in the table, cable selection affects both the maximum number of controllers allowed on the trunk, and the maximum baud rate. WorkPlace Tech Interface The MNB-ROAM-IA is the recommended communications converter for connecting WorkPlaceTech, including the WPT Commissioning and Flow Balance Tools, to an MS/TP trunk. It is supported in versions 5.7.1 and later. A converter that had been recommended earlier, the B & B Electronics model USOPTL4, was found not to operate reliably at speeds above 38.4 K baud. (See Direct MS-TP Connection with B & B Electronics Converters (Revised) - TB08-02-02 for details). The MNB-ROAM-IA supports Bluetooth wireless connection between WorkPlace Tech suite and the MS/TP network, for distances up to about 40 feet. One external Bluetooth adapter has been tested and approved - the Belkin USB adapter. (See Supported models of Bluetooth adapters with WorkPlace Tech for details). A problem we have seen with some MNB-ROAM-IAs is when trying to add Bluetooth device, the Bluetooth Wizard identifies it as "Serial Port Device, Unknown: Major(0), Minor(0)" instead of "tac-RoamIA:xxxxxxxx" where xxxxxxx is the serial number. There is no way for WPT to use the ROAM-IA if the computer can’t pair with it. Currently, there is no known solution, other than replacing the device. Divide and Conquer This is a strategy for dividing a bus into smaller sections in order to isolate a controller or section of bus that might be causing communication problems. The general idea is to divide the bus in half, and see if communications are possible from one end to the other end. If not, divide each half again, and continue until the problem(s) are found. Reference Documents F-27360 TAC I/A Series MicroNet BACnet Wiring, Networking, and Best Practices Guide F-27358 TAC I/A Series MicroNet BACnet Workplace Commissioning Tool and Flow Balance Tool User’s Guide F-27456 TAC I/A Series MicroNet BACnet MNB-70 Zone Controller Installation Instructions F-27345 TAC I/A Series MicroNet BACnet MNB-300 Unitary Controller Installation Instructions F-27346 TAC I/A Series MicroNet BACnet MNB-V1, MNB-V2 VAV Controller Installation Instructions F-27347 TAC I/A Series MicroNet BACnet MNB-1000 Controller Installation Instructions F-27419 TAC I/A Series MicroNet BACnet Smoke Control Systems Manual

Issue When ordering an MNL-10Rxx, MNL-15Rxx, or MNL-20Rxx controller, is the controller base included? Environment MNL controllers; MNL-10Rxx, MNL-15Rxx, or MNL-20Rxx Cause The web pages on iPortal do not described whether or not the base is included. Resolution The base is included when ordering any of these MNL controllers.

Issue How do you access BACnet MS/TP devices under a UNC without making a direct connection to the MS/TP bus?  Tunneling is supported with LON and ASD devices but there is no tunnel client for BACnet. Environment WorkPlace Tech Tool release 5.7.x UNC with BACnet MS/TP devices Cause Want to connect WPT through the UNC to access the MS/TP network attached to the UNC Resolution Tunneling is not required to access MS/TP devices under a UNC. Since the UNC is already a BACnet device because it has BACnet MS/TP devices connected to it, you can enable BACnet-IP or BACnet-Ethernet on the UNC.  Once either of these protocols have been enabled, the UNC then acts as a BACnet router allowing BACnet communications to the MS/TP devices directly via the ethernet connection to the UNC.

Issue Can a Niagara R2 UNC and a SIGNAL software-based computer simultaneously communicate to and poll values from a GCM-84000? The UNC would be interfaced serially to the GCM and SIGNAL would communicate over the GCM-LAN. Environment Niagara R2 UNC with the Network 8000 GCM driver, all versions SIGNAL, any version GCM-84000 series GCM-86000 series Cause The GCM cannot adequately process polling from more than one HMI. Resolution Although this architecture is physically possible to configure, it goes against the Best Practices of the Niagara Network 8000 Serial Driver.  Here is the excerpt from the Best Practices section of the driver manual (F-27070): When using the  I/A Series Niagara Framework to poll a GCM network while simultaneously polling the same system with another Human Machine Interface (HMI) problems can occur.  It is recommended that if the  I/A Series Niagara Framework is to be used it should be the only system polling the  NETWORK 8000 hardware. In particular, this should be noted that in the case of certain HMI systems (InVue™ and UltiVist™, for example), it may not always be obvious that there is something else polling the same hardware. These systems could be polling the same hardware by the Ethernet connection.

Issue License form does not list the BACnet MS/TP driver. Environment I/A Series R2 UNC-410 I/A Series G3 ENC-410 Cause License request for the UNC-410 or ENC-410 does not list an option for the BACnet MS/TP driver. The UNC-410 / ENC-410 does not support any RS-485 drivers because the RS-485 port is not electrically isolated. These controllers do support BACnet integration via BACnet-IP or BACnet-Ethernet. Resolution If BACnet MS/TP integration is required, use the UNC-520 or ENC-520.

Issue When using a Boolean Writable to reset the total of the NumericTotalizerExt  the total will reset when the ENC reboots. Environment G3 (Niagara) ENC version 3.4.64 & 3.5.25 were tested but all other versions of G3 should function the same way. Cause The resetTotal slot for the NumericTotalizerExt is an action slot so any data coming across its input will reset the total.  When the station is starting up the boolean writable point being used for reset is initialized which sends data across the link and resets the total. Resolution The proper way to reset the NumericTotalizerExt total is with a trigger object.  There are Interval and Daily trigger objects available in the kitControl palette inside the Control Palette folder.  Alternatively there is a TriggerSchedule object available in the Schedule palette that can serve this purpose.   If using an Interval or Daily trigger object link the Fire Trigger output from the trigger object into the resetTotal slot of the NumericTotalizerExt.  If using the TriggerSchedule object link its trigger output to the resetTotal input of the NumericTotalizerExt. 

Issue At times it is helpful to know the default IP address of a new MNB-1000 and it is not in the documentation. Environment All MNB-1000 controllers regardless of firmware version ship from the factory with a default IP address. Cause Connecting to an MNB-1000 for the first time after it is shipped from the factory. Resolution The default IP for all MNB-1000 controllers when they are shipped is 10.1.10.2.

Issue TIP License for the WorkPlace Tech Tool (WPT) software is about to expire.  What is the procedure for requesting a renewal of that license? Environment WPT 4.0.x  used by an engineer of a sales partner or branch office  WPT 5.x.x used by an engineer of a sales partner or branch office  Cause License expires 365 days after being unlocked. Resolution Please run the "Purchase WIBS Software" or "Purchase WorkPlace Tech Software" from the desktop of the computer.  The label on the displayed ICON will be dependent on the version of the WorkPlace Tech Tool software installed on the computer. On the "Purchase Information" screen, select the next available WP-TECH-50x license where x = E, R or R#.  See NOTE below, if there are no more R## license renewal entries available. Click the "Add to order button".  The requested license will appear in the "Order list". Click the "Accept Order" button and save the order form to your computer. Click the "Done" button to close the "Purchase Information" window then click "Done" to close the main purchase/unlock window. Email the saved license order form (from step 3) to IASeries.WIB_Order@schneider-electric.com.  The license unlock code will be emailed back to you typically within two working days. NOTE:  Download the WPTLExtractor.exe on The Exchange Extranet. This exe file will update the licensing information on the computer to allow for up to (15) - 365 days license renewals.  Please see the Technical Advisory Bulletin TPA-RKFD-09-0025 for additional information.

Issue The XPSI/PSI software can be used to manage & program ASD devices under a GCM.  Is it possible to configure the station running on an ENC to allow the PSI software to be directly connected to the ASD bus under the ENC? Environment ENC-520 with system software including the tacASD driver Cause The PSI software will not properly communicate properly with the devices on an ASD bus network if there is a GCM, UNC-520 or ENC-520 on the same bus unless the PSI software is configured in the "PSI under GCM" mode and the parent controller is configured to recognize the PSI software. Resolution The ENC-520 station database can be configured to support the simultaneous use of the PSI software on the ASD bus. To configure the station for use with the PSI software, the PSI object must be copied from the tacASD palette into the ASDNetwork container of the ENC station database.  No configuration of the object is required for proper operation.

Issue When doing a LON interface to a third party device the Lon Link Manager displays some links with a status of “service type error".  This has been reported specifically with York and Field Server devices but can occur with other manufacturers as well. Environment G3 (Niagara) ENC, R2 UNC Cause The default service\link type in R2 and G3 is “standard”, but some third party devices require one of the other types. Resolution Typically the service\link type cannot be changed in the third party device so the default service\link type for the SNVT(s) in question must be changed in the R2 or G3 interface.  Reference the R2 LonWorks Integration Guide chapter 8 "Link Manager" or G3 LonWorks Guide chapter 3 "About Lon Link Manager" for details on changing the service\link type.  

Issue Is there any support with Niagara R2 or G3 for Apple devices (iPod, iPhone, iPad)? Environment I/A Series R2 and G3 (all versions) Apple iPhone, iPad Android Cause Mobile device apps do not currently support Java script, and third party versions have not been validated by Tridium.   Resolution There is currently no support for the use of Apple devices with Niagara R2 or G3.

Issue Customer has a specification requirement to be able to open and edit MNL or MNB controller application files via a link on the associated I/A Series (Niagara) G3 graphic screen. Environment I/A Series (Niagara) G3 ENS Server Cause Specification issue. Resolution A WorkPlace Tech application file can NOT be opened automatically via a I/A Series (Niagara) G3 graphic link for the following reasons: Workplace Tech does not have a provision for opening an application file from the command line. The WorkPlace Tech Tool software would have to be installed on each computer that needed to open an application. The WorkPlace Tech Tool software would need a separate license for each computer on which it is installed. There are no provisions for centrally managing a shared WorkPlace Tech application library. A WorkPlace Tech application CAN be viewed via the Visio Viewer application.  This can be performed via a graphic link provided that the Visio Viewer application is already installed on the computer being used to view the application file.

Issue Can not enter the unlock code in WorkPlace Tech Purchasing Software, the “Unlock” button is grayed out. Environment WorkPlace Tech Tool software, release 5.7 or newer Cause WorkPlace Tech Purchasing Program was not properly closed after the codes were generated.  The Purchase program was closed using the “X” button, not the “Done” button.  Registry and file information does not get saved to the computer when the purchase program is closed using the “X” button. Resolution Re-run the purchasing program and select the same options. This time close the purchasing program using the "Done” button, not the “X” button.

Issue A Niagara R2 UNC has been operating for more than two years communicating with ASD devices.  Recently, the station stopped polling them without any external influence.  The ASD devices remain online and operational but the UNC station stopped polling them.  A reboot of the UNC resolved the issue.  What caused it? Environment Niagara R2 UNC-520, version 522 or older Cause An issue related to a timer rollover event caused the UNC system time to stop updating if the UNC has not had a reboot in 2.26 years.  This, in turn, stopped the ASD driver from polling since it relies upon the system clock. This issue affects other drivers as well. Resolution The short-term solution is to reboot the UNC before 2.26 years (or 828 days). The ideal solution is to upgrade to version r2.301.529.  The polling issue was fixed in this version.

Issue Can the FX-40 license be upgraded from version 3.3 to 3.5, and can a feature ("jcin2") be added to it? Environment I/A Series (Niagara) G3 Cause A branch / partner office is working with a customer building that has a FX-40 installed in it and wants to program it. Resolution Schneider-Electric cannot process the license file from a Johnson Controls FX-40 (equivalent to an ENC-410).   Both the upgrade to version 3.5 and the addition of the "jcin2" feature must be processed through JCI.

Issue A computer was installed with version 3.5.34 of Tridium's Vykon-branded Niagara AX and Schneider-Electric's TAC-branded Niagara G3.  An error appeared indicating that the core distribution files were missing. Environment Niagara G3 Workbench Cause The sw directory was missing under the 3.5.34 directory. Resolution Un-install both versions and re-install just one of them. The Vykon-branded and TAC-branded licenses files can be kept in a separate directory and swapped in-and-out as required.

Issue A GCM has lost its database and an older backup exists. The backup was done with SIGNAL software. Since then, the SIGNAL host computer was replaced. After placing a copy of the older backup in the UPLOAD directory, SIGNAL's download feature does not recognize the file. Environment SIGNAL for Windows 95/98 (version 4.4.1) SIGNAL for Windows XP (version 5.0.0) GCM-84000 series GCM-86000 series Cause The updown.dat "index" file used as reference by SIGNAL's download feature does not exist. It must contain at least one entry indicating that a backup copy of the GCM database exists in the UPLOAD directory. Resolution Even though the GCM lost its database, use SIGNAL's upload command to create a new backup copy of the GCM.  This process will create a new updown.dat "index' file and a file containing a backup copy of the GCM database.  The filename will be similar to:  UP016724.G1 Using Windows Explorer, go to the SIGNAL\UPLOAD directory and rename file UP016724.G1 to test.G1 Paste a copy of the older backup file and rename it to match the filename created in step 1 (UP016724.G1) Return to the SIGNAL desktop and perform a download.  SIGNAL will proceed to use the older backup file that was renamed. When the download is complete, review the database in the GCM with Terminal Mode to ensure all blocks are working and to make any programming changes. 

Issue Is the LCMA-103 (UIO board) interchangeable with the GCMA-106 (SIO board)? Environment LCM-84110, LCM-84210, LCMA-103 GCM-84111, GCM-84121, GCM-84211, GCM-84221, GCMA-106 Cause Not applicable Resolution No, the LCMA-103 is not interchangeable with the GCMA-106.

Issue The Curve Fit Object not functioning in MNB / MNL controllers.  Its output always reads ‘NA’ regardless of the input. Environment MNB controllers (all versions), MNL controllers (all versions) Cause N/A Resolution 1. Open the Curve Fit object’s properties in WorkPlace Tech 2. Change Data Point values “X1’ and “Y1” from “0” to “1” 3. Compile and download the application to the controller 4. Reopen the Curve Fit object’s properties in WorkPlace Tech 5. Change Data Point values “X1’ and “Y1” from “1” back to “0” 6. Recompile and download application to the controller again An additional alternative is to use non-zero values for Data Points "X1" and "Y1" (e.g. 0.01). The curve fit object should function correctly now. 

Issue Resizing the drawing from 11"x17" to 17"x22" just enlarged the size of the objects.  No additional space was available for more objects. Environment WorkPlace Tech Tool software (any version) Supported version of Microsoft Visio Cause Changing the Visio "Printer Paper" size does not resize the WPT drawing page size. Resolution Both the Device Definition page and the Background page needs to be resized and the resizing is a two step process. Select "Background" tab From File menu, select "Page Setup" Click "Page Size" tab - this window shows current drawing page size Select the desired drawing page size either by selecting a pre-defined size or a custom size.  We distribute our pre-defined application files with the page size set to 25% oversize (for printing on 11x17 paper) -- custom size 13.75" x 21.25" Click "Print Setup" page and select your printer paper size in the first field (we use Tabloid (B) 11in x 17in) In the Print Zoom section of the window, select Fit to 1 across x 1 down Click OK to save the settings and close the window. Select "Device Definition" page and repeat steps 2 through 7 on that drawing page. If there are any other pages in the application drawing, such as custom object pages, repeat step 8 (including 2 through 7) for each of those pages.