There are four models of the Versa-Tech recloser. They include the Versa-Tech LT, also known as the Versa-Tech Light, the Versa-Tech I, which is the first generation of the Versa-Tech released in 2007, the Versa-Tech II, which added numerous features and functions to the Versa-Tech I, and the Versa-Tech XC, which is the newest model offering extended communications. In all cases-- all four cases-- the design is virtually the same.
One of the key things that would motivate a user to go one direction or another is the amount of line current needed to power the radio on board any of these devices. In the case of the Versa-Tech LT, Versa-Tech I and Versa-Tech II, the line current needed to power the radios continuously is 10 amps. In the case of the Versa-Tech XC, that requirement drops to 6 amps. Some customers would rather have radios communication available at lower amperage, so that line personnel do not have to get out of the truck and toggle the red handle to wake up the radio on more lightly loaded lines. That is one motivation in moving towards the Versa-Tech XC. Another motivation to move to a Versa-Tech XC is access to the line-powered on-board SCADA cellular modem that you can attach to the recloser.
Between the Versa-Tech I (and LT) and
the Versa-Tech II (and XC), one of the key differentiators is a requirement for
custom curves-- where perhaps the 11 standard curves that come in the
Versa-Tech I and LT are not sufficient and there is a need to really fine tune
the coordination. The custom curve options as well as the additional standard
IEEE, IEC and ANSI curve option available is a motivator for a customer to jump
from either a Versa-Tech LT or Versa-Tech I into the Versa-Tech II and
Versa-Tech XC models.
Another consideration when choosing a specific Versa-Tech model is if you have requirements that call for 8,000 amps of fault interruption and/or 400 amps of continuous current-- which is more typically seen closer to the substation-- then the Versa-Tech I, the Versa-Tech II, or the Versa-Tech XC fulfill those requirements. Users that do not require that level of duty, such as only requiring 100 amps of continuous current and 4,000 amps of fault interrupting capability can fulfill those requirements with a Versa-Tech LT.
The lower continuous current rating and fault interrupt capability are some of the reasons why we call it the Versa-Tech LT, i.e., ‘Light’. It is a lighter version of recloser in the Versa-Tech family. The Versa-Tech LT tends to be a better fit mid-span, or midpoints on the distribution line and towards the end the line where your line current requirements are not as high as closer to the substation.
In terms of mobility and access to these devices, there are more and more users utilizing tablets and smartphones and computers to access these devices. So another reason why users may select either a Versa-Tech II or a Versa-Tech XC is the added security levels that we were employed in communicating with those two models. For the Versa-Tech II and the Versa-Tech XC, there is a credentials hierarchy of access. That means that you not only need to have a password to access the WPA2 secured Wi-Fi environment of the device, you also need to declare credentials-- a username and password to access the control board of the device through the user interface. For the Versa-Tech II and the Versa-Tech XC, there is a hierarchy of 5 different user levels. An administrator can perform any function on the device, whereas a basic user may only be able to view parameters and download a log from the device. The benefit of having this hierarchy is, of course, customers are able to deploy user name and credentials to, e.g., a lineman, to only be able to download a report and not have access to modifier users, perform firmware upgrades, or modify settings.
Additionally, for users that want to dial into the functionality of the device and fault logistics as handled by the device, the Versa-Tech II and the Versa-Tech XC provide an extra layer of technical benefit in the form of a device log. In the device log there are timestamped entries of events taking place in the device firmware, i.e., initial detection of faults, close commands to the bottle, etc. These devices also offer an Audit Log which records and timestamps each time a user access the device and notes what changes are made. For example, when a user logs into the device, that becomes a timestamped event in the audit log. If a customer needs to determine any interaction that anyone has had with the device, he or she can pinpoint and identify who has been accessing the device. More importantly, if it is a user that has the credentials allowing them to make changes and that user does make a change, the device will record the fact that user changed the protection settings.
With the Versa-Tech I and Versa-Tech LT are somewhat limited as far as the amount of information collected. The Versa-Tech LT and the Versa-Tech I have smaller memory banks. In those two devices, only the last 80 events and 1048 demand log entries are recorded. The Versa-Tech II and the Versa-Tech XC both collect 256 events and 2160 demand log entries. In addition, a user can program the collection of the demand log, or load profile, data from five minutes to 60 minutes. So, it is user configurable, whereas in the Versa-Tech LT and Versa-Tech I, it is hard coded that demand log entries occur every 60 minutes with a timestamped average value and peak value.