Backing up the UPS

Power loss is a critical failure, thus much money is spent to prevent or mitigate commercial power interruptions in broadcast facilities.  Backup generators and Uninterruptible Power Supplies (UPS) are the first lines of defense against commercial power interruptions.  It is prudent to research products and check reliability and interoperability when specifying and installing these systems.  However, even the best mechanical and electrical systems will fail, often at the worst possible time.  The UPS has a startling tendency to shut down, often at the worst possible moment, due to some internal control circuit or something similar.   This can happen when commercial power is being supplied without interruption.  The net result is some critical piece of equipment is now dark and the station is off the air.

Eaton Automatic Transfer Switch and UPS
Eaton Automatic Transfer Switch and UPS

There is a solution: The Eaton EATS EPDU TPC 2234-A Automatic Transfer Switch.

Eaton EATS EPDU
Eaton EATS EPDU

With this unit, the primary plug is connected to the output of the UPS, the secondary plug is connected to the commercial power source.  If the UPS fails, the load is automatically transferred to the commercial power.  Typically, the commercial power is also backup up with a generator.  The secondary plug can also be connected to a second UPS.  In theory, having two UPSs connected in parallel via an Automatic Transfer Switch would increase the Mean Time Between Failure (MTBF) by 50%.

UPS Eaton ATS EPDU block diagram
UPS Eaton ATS EPDU block diagram

The Eaton products come with a variety of options, including basic network monitoring, advanced network monitoring, switching, and management.  Those features are available via Ethernet or serial data port.

Multiple layers of redundancy is the best method to avoid those late-night, weekend, or holiday phone calls.

FM Fool website

Just for geeks, the FM Fool website is.  Nonetheless, it is a cool site to look at and can be used as a tool to find out what stations are available in any certain area.  Using the FCC database and terrain profile, it will print out a radar plot of all signals for any address in the US:

FM Fool Radar plot
FM Fool Radar plot

This plot is for my house based on a 30-foot outdoor antenna and includes all FM stations that are even marginally receivable.  We kind of live off to the side of nowhere.

The transmitter database was last updated on July 5, 2012.  Longer bars represent stronger signals.  Details about each transmitter are provided in the table to the right of the plot.

This is a companion site for the TV Fool website.  If you want to see what off-air TV signals are available at any given location, this is the way to do it.  A few years ago, I was thinking of getting rid of the Cable TV in favor of off-air reception.  Unfortunately, there are only a few off-air TV channels available at my house.  Therefore,  I threw out the TV.  Problem solved.

We are experiencing technical dificulties, please stand by

There appears to be some issue with my version of WordPress, the server in use, and the version of PHP. The ISP recently upgraded my server and migrated my site over to a new unit, which was supposed to be transparent. Right. I am working with the ISP to resolve these issues as quickly as possible and return to my regular blogging.

In the meantime:

Update: All fixed, for now anyway. Something about a mismatched password in the backend. To all those that tried to comment, my apologies. It should all be working correctly now.

SSAC BKON tower light flasher

Tower light outages are fairly typical in this business and I have spent a fair amount of time at various tower bases poking around in the junction boxes looking for trouble. Over the years, I have replaced several old mechanical tower light flashers with these SSAC solid-state units. The SSAC units are nice, in that they have a zero voltage turn-on, which tends to extend the service life of incandescent bulbs.

This unit appears to have taken the brunt of a lightning strike:

SSAC BKON FS155-30T tower light flasher
SSAC BKON FS155-30T tower light flasher

I would hazard a guess that lightning struck the top part of the beacon housing where the bulb socket is located, then traveled down the AC line to this device.  Luckily, it appears the wire insulation inside the conduit to the beacon fixture is still intact.  Sometimes, under high stress, wire insulation can fail, as it is most often rated for 600 volts maximum.  I have also seen that happen on more than one tower, especially if water has made its way into the conduit.

SSAC BKON tower light flasher
SSAC BKON tower light flasher

Side view, this was mounted on a hot AM tower, but was not the unit designed for high RF environments. Those units are denoted with an “RF” suffix. The difference between the two, the RF models have bypass capacitors installed internally.

SSAC FS155-30T destroyed by lightning
SSAC FS155-30T destroyed by lightning

Lightning path to ground, through the bottom of the case.