Issue
INFORMATION BULLETIN - Interface Expander 2 SmartSlot Card Smart Signalling Information and Explanation
Product Line
- UPS Device Management
- Interface Expander 2 - AP9624
- Supported UPS Models (as outlined in knowledge base article ID FA176135)
Environment
- All AP9624 serial numbers
- All AP9624 firmware versions
Cause
This information is provided to assist with understanding of the AP9624 applications, especially those that are different from the original AP9607 Interface Expander SmartSlot Card that users may be accustomed to. It is intended to be an appendix in relation to a few references within the AP9624 User's Guide. The latest version of the AP9624 User's Guide is available here -> http://www.apc.com/resource/include/techspec_index.cfm?base_sku=AP9624&tab=documentation
Resolution
Master servers and smart signalling
Certain UPS types, upon insertion of the AP9624 Interface Expander 2 to the onboard SmartSlot, will have their RJ-45 serial ports forced to simple signaling only. These UPS types begin with the following model prefixes and will have a RJ-45 style serial port, as noted:
- SURTD
- SRC2KUXI, SRC3KUXI, SRC3KUXIX709
Confirmed shutdown mode and the UPS port
The aforementioned UPS models in the "Master servers and smart signalling" section of this knowledge base will behave in the same manner as "older generation" devices (which can be defined as those with a DB-9 style serial port). "Newer generation" units are defined as those that utilize an onboard RJ-45 style serial port, except those specific models listed above. More information on UPS "generations" is available here -> Knowledge base article ID FA230533.
For most newer generation UPS devices, DIP switch #4 should be in the 1 (up) position. In this mode, when on battery the Interface Expander 2 waits for all "connected clients" to signal shutdown before commanding the UPS to shutdown. The term "connected clients" is used because the Interface Expander 2 has hardware circuitry that lets it know whether there's a client connected to either of the DB-9 ports. However, the Interface Expander 2 cannot tell whether there's a client connected to the communication port directly on the UPS (or if its even possible to connect anything to this port - refer to the "Master servers and smart signalling" section of this article). This is why DIP switch #4 is used in this mode - to indicate to the Interface Expander 2 whether there's a client connected to the communication port directly on the UPS (also called the upstream port) of the Interface Expander 2. If the DIP Switch is not set properly, the Interface Expander 2 could wait indefinitely for a client attached to the UPS serial port that it cannot tell if it is present or not.
Furthermore, on newer generation units that support smart signalling on the UPS communication port, the smart client must have their UPS turn off delay set appropriately as to allow long enough for all connected clients to shutdown. Otherwise, it may be possible for the client on the smart port on the UPS to shutdown the UPS before the simple signalling clients attached to the Interface Expander 2 have completed their shutdown and signalled the Interface Expander 2 to shutdown. This is because the Interface Expander 2 and the communication ports on the UPS are completely isolated from each other, unlike in older generation devices, where they were on the same communication chain or "upstream/downstream" from each other.
Additional information
| UPS Model Name Prefix | UPS Serial Port Connector Type | System Configuration with AP9624 Interface Expander 2 in Confirmed Mode with DIP Switch 4 Down | Valid or Invalid? | Reason why Configuration is Valid or Invalid |
| SU, SUA, SUVT/G3500, SURT, SURTA, SRC, Symmetra LX | DB-9 |
| Invalid | There is no client connected to the UPS "smart" serial port. The Interface Expander 2 would wait "forever" for something that will never happen. |
| SU, SUA, SUVT/G3500, SURT, SURTA, SRC, Symmetra LX | DB-9 |
| Valid | Since there is a client on the UPS "smart" port, the Interface Expander 2 will wait for the smart client to signal a shutdown and complete it's full turn off/reboot process. The Interface Expander 2 can "talk" to the UPS communication port with this UPS architecture. |
| SMT, SMX, SRT, SRC | RJ-45 |
| Invalid | There is no way on these specific UPS types for the Interface Expander 2 to know whether or not there is a "smart" client connected to the UPS port due to the UPS architecture. The DIP Switch signifying if smart client exists must be done by the user. The user needs to put DIP Switch #4 in the "up" position and make sure their maximum required delay is set accordingly to allow time for all "connected clients" to shutdown, as to not initiate a pre-mature shutdown before Interface Expander 2 clients have had a chance to shutdown. |
| SMT, SMX, SRT, SRC | RJ-45 |
| Invalid | This configuration is invalid as the "upstream" port of these UPS models is not connected internally to the Interface Expander 2 but instead has a direct UPS connection. Therefore, from the Interface Expander 2's perspective, it should not have an upstream client awaiting confirmation because it will not be able to talk to that UPS port and receive a confirmation. |
| SURTD, SRC2KUXI, SRC3KUXI, SRC3KUXIX709 | RJ-45 |
| Invalid | These UPS types only support simple signaling on their RJ-45 UPS communication port. Since the client is not "smart", the DIP switch needs to be set manually by the user too in order to tell the Interface Expander 2 whether there is a client connected or not on the UPS port. |
| SURTD, SRC2KUXI, SRC3KUXI, SRC3KUXIX709 | RJ-45 |
| Valid | These UPS types only support simple signaling on their RJ-45 UPS communication port. Since the client is not "smart", the DIP switch needs to be set manually by the user too in order to tell the Interface Expander 2 whether there is a client connected or not on the UPS port. In order to do that, DIP switch #4 should be down. |