Need help with electric company flash off and on power

[Tommy Fermanian]

Hi all, we are in a mountainous area and electric company lack of maintenance in their equipment makes it that we get electrical flash interruptions, either quick reduction of power or almost instant off then back on. Being an 8 Plex, the major problems are Christie projectors. Servers are battery pack protected so are sound processors.hence features keep going,sound format stays on, but projector lamp turns off and we get “ unexpected turn off” message.we then punch light on, projector goes into cool down, we re punch light on and things keep going, we then have to stop feature back up 5 minutes or whatever, multiply these maneuvers by 8 times you get the picture.Suggestions include massive battery pack to keep,projector bulb on, this is expensive an unaffordable for us, in the old 35mm days, lamp houses used to turn right back on automatically, Would there be an automation fix or electronic way to achieve this? Any ideas? When flashes like these happened, windy here last night, we had 5 interruptions , you can imagine the running around in the projection booths plus dealing with irate clients whom can’t fathom that it’s the electric company’s fault and not our equipment? Any affordable ideas ? Thanks !

[Marcel Birgelen]

If you're on an unprotected leg of your network with long overhead power lines, you're easily prone to frequent outages during high-wind situations, when power lines start to swing and the conductors get too close together, especially if the power company has done nothing to improve the situation. Running new high-voltage lines is a costly business, so they often postpone those works as much as they can.

But usually, power companies solve this problem by installing capacitors in their network to compensate for such things, especially if you're in an area prone to those kind of issues. You really should urge your power company to install those to remedy the problem. Those can be installed on multiple levels, usually even at your local network teminal.

If it's really just a sub-second interruption, you should ask your local electrician if he can't provide a condensator-backed solution that compensates for those short interruptions and is up to code with your electric installation. Those systems should be far cheaper than battery-backed UPS systems, which need to be pretty massive to support typical xenon lamp house projector loads.

[Steve Guttag]

Of the DLP companies, only Barco really has thought about this and has the option of returning to the same state if a momentary power interruption occurs. Christie refuses. You'll need to come up with an external automation system (e.g. Eprad eCNA , Integ JNIOR or some other configurable system...even QSYS) to create an auto-on. However, you need to think it out in that you only want the lamp to restrike if the lamp was in the on-state when the power failed. You also don't want it to fight the user if they should turn it off via the projector's controls.

Shoot, for Christie, it would be nice if such an automation also overcame their numerous "unexpected lamp off" due to most anything...nominal door switches, serial communication...etc.

[Ed Gordon]

All three basic uninterruptible power supply (UPS) technologies have their place in protecting today’s distributed IT infrastructure especially on the network edge. Each technology has its advantages and each may be necessary for configuring cost effective power protection, especially in complex systems. Selecting a UPS for your particular application requires an examination of a number of factors. The load size, location and criticality of the equipment to be protected are key, as well budgetary considerations, when choosing a UPS for power backup.

The three major types of UPS system configurations are online double conversion, line-interactive and offline (also called standby and battery backup). These UPS systems are defined by how power moves through the unit.

Online Double Conversion

AC power is stable and clean upon generation. But during transmission and distribution, it is subject to voltage sags, spikes and complete failure that may interrupt computer operations, cause data loss and damage equipment. When it comes to safeguarding critical IT loads, only online double conversion technology protects fully against all these power problems, providing the highest levels of security for networks.

An online UPS system is usually called double conversion as well because incoming power is converted to direct current (DC) and then converted back to AC. This AC-DC/DC- AC design ensures an increased degree of isolation of the load from the irregularities on the main supply.

The online UPS takes the incoming AC power supply and converts it to DC using a a rectifier to feed the battery and the connected load via the inverter so that no power transfer switches are necessary. If the main AC input fails, the rectifier drops out of the circuit and the batteries keep the power flowing to the device connected to the UPS. When AC input power is restored, the rectifier resumes carrying most of the load and begins charging the batteries.

Because power runs through an online UPS continually, output is a perfect sine wave. This type of UPS protects the critical load from virtually all power disturbances, including subtle harmonics and waveform distortion.

This means the quality of power from online UPS is significantly better than that of other technologies. Offline and line-interactive technologies reduce the impact of spikes, surges and sags by either clipping the peaks and valleys, boosting power or switching to battery backup. Within the normal track of an electrical sine wave, however, most power fluctuations are left alone. Online UPS regenerates the sine wave, not just conditioning of the raw utility supply.

An online UPS delivers continuous, high-quality AC power to equipment with no break when transferring to battery, protecting equipment from virtually all power disturbances due to blackouts, brownouts, sags, surges or noise interference. A true online, double-conversion UPS provides 100% power conditioning, zero transfer time to battery, no change in output voltage and better transient suppression than line-interactive units.

Online double conversion is the most common UPS mode of operation used for protecting large data centers by providing the highest level of power quality to the load always. Online systems also provide frequency regulation, essential for use with backup generator systems to protect from variations common at generator start up.


Line-Interactive

Line-interactive UPS systems provide both power conditioning and battery backup. This technology is particularly effective in areas where outages are rare, but power fluctuations are common. Line-interactive UPS systems support a wide range of input voltage fluctuations before switching to battery backup.

Beyond battery backup, line-interactive UPS provides far better control over power fluctuations then offline systems. The critical advantage of line-interactive UPS is the voltage boost circuitry and the range of input voltage that that UPS accepts. The wider the range, the more total protection you will have.

Line-interactive UPS technology provides power conditioning with a 4-6 millisecond break in power when transferring to battery back-up and protects against the most common power problems experienced in a network. Here the UPS also monitors the voltage level and balances under and over voltages. This technology provides a good choice between reasonable protection and moderate operating costs.

With line-interactive UPS, the inverter becomes part of the output and is always on. The inverter can operate in reverse to charge the battery while AC input is normal, and switch to battery power when input fails, which provides filtering and voltage regulation. Line interactive UPS systems rely on the battery to condition power so this type tends to drain its battery more frequently than online UPS systems that condition power through the double-conversion process.

When AC input power fails, the unit’s transfer switch opens and the power flows from the battery to the UPS output. With the inverter always on and connected to the output, line-interactive UPS provides additional filtering and yields reduced switching transients when compared to a standby UPS. Line-interactive UPS systems are typically used in rackmount applications below 5000VA.


Offline/Standby/Battery Backup

Offline UPS, also called standby UPS or battery backup, is a cost-effective choice. Better offline UPS systems switch to battery fast enough to prevent power anomalies and ride out short outages. An offline UPS protects against most spikes, but doesn’t maintain perfect power during minor sags and surges.

The key to offline UPS quality is the range of power the unit will except before switching to battery backup. The wider the range, the less drain on the battery and the more backup time available when the power shuts off. The more times the UPS switches to battery backup, the shorter the battery life.

Offline UPS technology will protect from most power spikes by clamping down on excess voltage and help ride out more than 90% of all outages. An offline UPS system passes utility AC power straight through the unit, past a transfer switch, to the output point where the protected load is connected.

When an input power failure happens, the built-in battery and the inverter, which converts the battery’s DC power to AC, are activated and connected to the output by the transfer switch. There is generally about a 6-8 millisecond break in power when transferring to battery back-up.

This technology is best suited for devices under 1500VA such as small offices, personal home computers and other less critical applications. Offline UPS is a good option for those requiring lower power capacity and cost. Offline UPS technology provides power backup protection for desktop equipment, gaming consoles, workstations, wireless networks and other electronics. During power outage, it provides enough runtime to save work in process and complete an orderly shutdown of equipment. In addition to power backup, most offline UPS systems offers basic surge protection as well.

Source: https://www.vertiv.com/en-us/about/n...f-ups-systems/


If all you can afford is a Offline/Standby/Battery Backup system, you may be out of luck. A Line-Interactive system might work. I once worked for a company that had a Online Double Conversion system for their data center. For less critical areas Offline/Standby/Battery Backup systems were used.

We had a situation where once a week around 2am, the Offline/Standby Battery backup would kick in and kill the file server located within their office. It turned out that the engineers would test the switch to battery once a week at 2am. The fix was to move the office server to the data center which ran Online Double Conversion system.

Your best bet is to invite some vendors in to assess you condition and make recommendations.

[Carsten Kurz]

Maybe it would be useful to rent a line-analyser first to get some idea about the nature of these outages.

[Bruce Cloutier]

It is somewhat amazing as to how much we expect services like power and Internet to always be there. If you do not want to be interrupted by a power outage then an investment in backup power systems is essential. For a commercial facility that clearly is expensive.

My personal experience with PowerWall where I had figured that having to reset clocks after a power glitch would be a thing of history, was surprising. It appears that lines are shunted to dissipate the energy of nearby lightning strikes. As a result, I've still had to reset clocks. I guess that is still better than having to replace equipment.

Presentation equipment however should take into consideration the impact on the experience and at least try to minimize it. Maybe they need a design with some Platinum? Use Blockchain or some verbal magic that they think impresses us.

Automation can help but the recovery is generally way too complex and specific to the equipment in use. First the controller needs to be protected from the power outage. It then needs to be given some way to detect the event. With that you still need to be completely aware of what should be happening at the very moment of power loss before anything tries to restart things. The JNIOR that is not protected by a UPS will reboot. The Series 3 reboot is lengthy as you all know. While the Series 4 boot is fast it still wouldn't know what was supposed to be going on let alone how to correctly (and safely) recover. It is likely that the steps needed too are not things that can be accomplished via protocol or relay closure.

We did include a ride-through power capability in the 412DMX. That controller can be unplugged for 20 or 30 seconds and not be affected. It is like a mini built-in UPS. That said, it is the component in that power supply function which became unavailable with the COVID shutdown and has kept us from producing the product until just lately. Then we could only build 100. The fate of that supply circuit awaits redesign. It is pretty cool though. Thwarts those of you who yank the power to cause a reboot. It was being evaluated as an update to the entire line but...

Designing fault-tolerant systems is a real challenge. I put a huge effort into making sure that our firmware update procedure was completely fault-tolerant. No bricking. You know how everyone warns not to remove power during an update. That is of no concern with the Series 4. Not simple to do. Making a fault-tolerant theatre is another matter altogether. It is possible I would think.

I suspect that some condenser backup system to insure the artistic quality of the content and regulate the flow of patrons at the box office would be even better.

[Marco Giustini]

If all you can afford is a Offline/Standby/Battery Backup system, you may be out of luck. A Line-Interactive system might work. I once worked for a company that had a Online Double Conversion system for their data center. For less critical areas Offline/Standby/Battery Backup systems were used

To keep Xenon lamps on you need a hell of a UPS
This is why he's got servers, projector electronics and sound processors under UPS protection - but amplifiers and lamps...

[Steve Guttag]

Bruce, we put the automation, server and projector electronics (and now QSYS systems, particularly if one CORE runs more than 1 screen) on a UPS. We tended towards double-conversion (online) UPSes and that is now trending towards 100%.

We use a basic 120V coil relay and tie that to one of the inputs of the automation. That relay is plugged into the same circuit as the UPS the backs up the automation. As such, the automation "knows" about a power event. We can then process the event as the client desires. Typically, we pause the show since the lamp and amplifiers will go out during a power event and, depending on the length of the event, the house lights will return to their up position when the power comes back. We also provide a "restart" switch that will run a routine that gets the show going again (lights down, lamp on, sound on, and starts the server).

The question comes do we immediately respond to a momentary power blip or do we wait for say 2-seconds to ensure that the lamp went out amps went off, lights came up...etc? Different equipment react differently to power blips...particularly those of 1-second or less. NEC, for example, is quite touchy on power blips and will drop their lamp out. Christie is also pretty fast on the trigger. It is possible, via numerous means to see if the lamp has gone out (Ethernet, optical sensor...etc.). But it is another thing to know if it should be out. You don't want an automation striking the lamp when it should be in the off state. It needs to keep track of what state it should be and to allow for user-intervention. That is where it can get complicated.

[Marcel Birgelen]

It's far too expensive for almost any medium sized business to put high-powered workloads like xenon lamps, HVAC and high-power amps on UPSes. It's nothing abnormal for power lines to rural areas to be more prone to short outages, as most of them aren't redundant, but anno 2023, there are practical solutions for power companies, that don't cost them a ton. The problem is, those solutions usually aren't available to those businesses directly, because you're most likely not allowed to install this equipment yourself.

Your power company really should install some of these:

pole-mounted-cap.jpg
Those are pole-mounted capacitor banks and they help to smooth out voltage dips due to short supply disruptions or peak loads due to stuff like inrush currents at other users in your neighborhood.

I'm not aware about your particular situaton, but since power is seen as an essential utility in many jurisdictions, you actually can hold your power company responsible for damages arising due to their failure of delivering a stable power feed to your premises.

[Gordon McLeod]

With the christies put the projector head on a UPS and the server
Then only the lamp will switch off
Add a relay across the mains to close a GPI contact on the IMB to put the server on pause
then all one needs to do is a reignite lamp (hot restrike) and unpause the content when the power is restored

[Mark Gulbrandsen]

I totally recommend the double conversion UPS's. I installed those exclusively and I only ever had to clean the air intake and replace batteries in them over the years. My recommendation is to still go upstairs and should the power stay off longer than the run time of the UPS, then manually shut the equipment down until the power stabilizes, and before the UPS batteries deplete.

[Harold Hallikainen]

[QUOTE=Marcel Birgelen;n33439]
Your power company really should install some of these:

pole-mounted-cap.jpg
Those are pole-mounted capacitor banks and they help to smooth out voltage dips due to short supply disruptions or peak loads due to stuff like inrush currents at other users in your neighborhood.

I don't believe capacitors on utility lines affect inrush or provide "ride through" of voltage dips. They, instead, provide power factor correction. Inductive loads, such as motors, have a low power factor causing the apparent power (VA) to be less than the real power (watts). The current through the wires is proportional to the apparent power. Adding capacitors across the line improves the power factor, reducing the current through the line, reducing power loss in the line (I^2 * R losses).

Harold
https://w6iwi.org

[Ed Gordon]

I totally recommend the double conversion UPS's. I installed those exclusively and I only ever had to clean the air intake and replace batteries in them over the years. My recommendation is to still go upstairs and should the power stay off longer than the run time of the UPS, then manually shut the equipment down until the power stabilizes, and before the UPS batteries deplete.

I had no idea they made smaller (afftordable!) double conversion UPS's. The last one I saw was the for a data center that was a small room filled with car batteries and a diesel generator.

[Mark Gulbrandsen]

I had no idea they made smaller (afftordable!) double conversion UPS's. The last one I saw was the for a data center that was a small room filled with car batteries and a diesel generator.

I only put in 1500 VA double conversion UPS. This only ran projector electronics, the server and monitor Was only intended to allow safe shut down of those items. I think it gave about a 12 minute run time. There are also versions of UPS that use external battery packs. So you are going to need something larger, especially if you want to keep the lamp lit...

[Jim Cassedy]

Trivial Anecdote: I've spent most of my so called 'career' working in older theaters, and it
was very common for them to have two separate electric feeds, from different transformers
to lessen the chance of power interruptions. I can think of several still in operation here that
have one power feed from the pole (or underground vault) in front of the theater, and a 2nd
feed from another pole or vault on the next block. It was switched automatically by a relay,
which worked quite well for tube amps and DC motor-generators which could tolerate the
500milliseconds or so it took to make the switch with barely a hiccup, - - but I doubt our
modern electronificated systems could deal with it as well. When I was sent to San Antonio
for DUNKIRK a couple of years ago, the large modern multiplex theater complex they had
me working at got it's power from two separate substations, since power interruptions and
outages were quite common during the huge thunderstorms they get in that part of the
country. We went through two or three big storms where the power sources switched while
I was there. The 70mm projector, and the Xenon lamps would 'burp' for a second but would
continue working. Same with the power amps. The only thing I had a problem with was the
DTS player, which I would have to wait for it to re-boot before re-starting the 70mm.
(Otherwise the show could have continued uninterrupted) After the 2nd power-outage I
realized that the UPS the DTS was plugged into wasn't really any good, so ran a power
cord from a 'good' ups in another rack and ran the DTS off that, and had no trouble during
the 3rd storm when the power went out for a few seconds.