Last week I had a classic case of inaccurate reporting of a fault description causing a lot of unnecessary callouts, tech time and wasted diagnostics measures.
The site is an apartment building with ZKTeco access control, doing a number of doors & 2 lift cars. The fault report was that both of the EC10 lift controllers were failing simultaneously and allowing free access to all levels. As you know, with ZKTeco there is no ‘master’ controller & thus no single point of failure. The fact that it was reported that both EC10s were faulting simultaneously implies something common to the 2 stand alone intelligent controllers.
My first thought in this circumstance is power, as both of the EC10s were initially on the same power supply. Perhaps ‘noisy’, perhaps a dead battery pulling it down. Initially, the first alteration on the site was a replacement battery. When this did not work the power supply was replaced with 2 smaller supplies with a backup battery. One for each of the intelligent EC10 lift controllers. The system still faulted.
My customer spoke to me & we arranged remote access to the site. Upon examining the event log, I ascertained what the fault was. Like most access control systems, the ZKTeco has a fairly
detailed event log, but until this point, nobody had bothered to spend some time (10 minutes is all it took) to actually look for ‘fault’ events in the log.
Upon examining the event log I found quite a few “Superuser open buttons” events, which of course is a user with Superuser authority level badging & thus toggling all floors to free access
or secure. Yes, it actually took all of 10 minutes to find & fix the issue, which ultimately was self inflicted by the end user (building manager) not following instructions or RTFMing.
The Superuser card presentations ONLY affected the lift car the user presented in, not both & looking at the event log it would have been very rare for both lift cars to have the fault at the
same time, even if the fault did not occur simultaneously.
This means the initial, and often repeated by the building manager, both failed simultaneously was totally in error & will end up costing the body corporate a lot of money for wasted
The lessons to learn
Do not trust the end users fault descriptions, always verify for yourself.
Use the event log. Most modern hardware has good event logging & will often tell the tale.