December 16, 2010

13 years on eBay

Chefash auctions enters its 13th year on eBay today.

When we started there was no paypal, just Money orders and checks.  It seems like only yesterday, I would stand in line at a shady convenience store getting $4.65 money orders for the beanie baby of the day.

Today, as a Powerseller probably from ebay's inception and with a flawless feedback rating, we deliver good value to our customers on that platform.
Shop here

December 14, 2010

Bypass Switches for UPS Units

Many high end UPSes offer Bypass switches on their systems.  These systems allow power to flow past the UPS, directly to the load.  The purpose is to allow the UPS to be serviced without interrupting the load.  Unfortunately, this feature is very expensive for some reason.

On smaller UPS systems, APC recommends a SBP3000, which retails for $300.
On larger 5-16kva units, APC recommends a SBP16KP, which retails for $900
Finally, get a large Symmetra 80kva unit and your bypass panel is a 42u cabinet called a PD60F6FK1.  This monstrosity retails for $14,000.
Essentially these bypasses are transfer switches.  And like many electrical things in the UPS world, they cost  almost 10 times more than they should.  The SBP3000 can be replaced with a 2pole 30amp switch ($40),  a small 60amp transfer switch ($200) replaces the 16KP thing, and a 200amp transfer switch ($900) can be wired to have the same effect as the PD60 thing.

So if you need a bypass, consider the APC units, but email if you want more info on these alternatives.

December 12, 2010

Random APC Part of the month IV

There is rack mount format, tower mount, desktop and now... wall mount UPSes.


APC's BackUP HS Series units are wall mounted UPS units designed for structured wiring cabinets.  SWC are those fancy panels that terminate your whole house music, networking or other low voltage system equipment.

Interestingly, this might be a good solution for wireless hotspots, alarm panels, and applications where there is no floor space for the UPS.

APC's says its a "a compete management and power protection solution for structured wiring and home networking applications. It provides the flexibility to remotely manage the UPS and control the outlets via Web browser."

For now we DONT carry it, but it does secretly intrigue me.  Buy it here

December 11, 2010

Comments on the 10kva UPS Units

10,000va Rackmount UPSes are very popular.  Both APC and Tripplite make units that fit this powerful UPS into a 6U tower system.

Unfortunately, they dont seem to last.  I have noticed that especially the APC SURT10000s (1096g3) seem to fail.  When we get in UPS units from liquidators, surplusers and off lease companies, I can almost predict how many will be bad given the models.  For us  most units come in at under 10% complete failure.  (some like the 2200va 3u [203] never seem to fail)  But looking at our graveyard of UPSes units, I see many 10kva units.  Checking my purchase logs, it has been almost 40% come in DOA.

Why?  My guess is like the poor showing of the Dell 3000va 2Us, APC has forced such a large power handling system into too small of a housing.  So in the real world, when people don't properly cool the unit and overload it, the heat slowly kills it.

My advice is to buy two 5000va (593g3) units.  Its always cheaper and easier to wire.  Only buy those 10kva units if that one piece of equipment needs 30amps of power and go with the Tripplite (to1096) since they have an external PDU that keeps the wiring outside the main unit.  Never just for a server array.

December 10, 2010

Lightest and Smallest 3000va UPS Ever

As more and more of you request our UPS units to be shipped across the country and world, some are asking first about the weight.

As I have mentioned, besides the heavy lead batteries, there are two UPS technologies that weigh dramatically different.  Online UPSes weigh less than Line Interactive types.  However, Tripplite, now has a 3000va 2U Line Interactive unit that is smaller and lighter than an APC 1500va.

The Smart3000RM2U or tl312 (tl312c) is only 17.5 x 19 and weighs 64lbs.  This is smaller than the APC 1500 2U (402b) at 18.0 x 19.

So if you need a light UPS to ship or a small UPS for road shows this is a great buy.

November 17, 2010

Sell without batteries

We get many requests to sell a unit WITHOUT batteries.   In general, we dont mind, but always warn our customers about an issue, especially if you plan to use old batteries from another unit.

  • This happens often, when you want to upgrade the unit to a larger size and use your existing battery system.
  • Each UPS has a charging rate based on the age of the batteries.  As the batteries age, the UPS charges them more.  Therefore our fresh unit we sell you will have its charger calibrated to charge the batteries as if they were new. Since yours wont be, this charging imbalance will shorten the life of your used batteries. 
  • Unfortunately, we cant calibrate the charger unit to half-aged, or 1 year old.
If you want to buy a unit without batteries, just email us and we'll give you a quick quote.

New Symmetra Line... the LXnXL

As per the previous posts, we have the regular, LX, small PM rackmount, and the big 3phase PX model line.   Now we have a few LX super duty units.  These single phase LX units are modern and have a built in extended run module attached.  They typically provide an hour of runtime even at half load.


They come in a 16kva frame, but can be built as 8, 12, 16 or 16N+1.

The one in the photo is brand new (which wont last long), but the others are late models 08-09 series.  I fairly certain they were developed after the original LX line.

October 26, 2010

240v 208v Challenges and magic Buck Boost transformers

I tend to answer a lot of questions about High Voltage systems (here, here, here) about its effects on UPS units.  

Today, we had a customer that wanted 240v for his equipment and another customer that wanted to use his 5000va 208v UPS in his 240v building.

Both challenges can be solved with Buck Boost transformers.  These affordable transformers step up and down voltage in a small frame by magic.

The customer that wanted 240volt for his equipment, bought one to plug in his wall and then plugged the 240volt UPS into it.  Then the UPS output was 240volt as he wanted.(Type 3u)

The customer that had a 208v UPS, but had 240v building power, plugged in the magic unit (Type 5d) and reduced the voltage to the UPS and lived happily ever after.

We sell 4 common configurations, all are Plug & Play easy, and are sized to the UPS you are using.  Notice, these units can only tweek the voltage, they are not full blown Step down 208v to 120v or Isolation transformers.  We have those as well.

Buying Guide for 7-10kva UPS units

When you want a large UPS, there 3 important specs to consider
  1. Is this for a single piece of equipment/panel? (or is for multiple loads)
  2. Are you prepared to hard wire this into your electrical system?
  3. Do you expect to grow and want an expandable solution?
1) If this large unit is to replace several small units, it might not be that great a deal to combine them.  One 10kva unit costs way more than two 5kva units.  ($1900 v $2500).   
 v.


2) The standard 30amp L630 outlet can only provide about 6000va of power.  Therefore if you want to use these larger UPS units, you need to have a new 50amp circuit hardwired or 50amp outlet  (both big bucks).   Many people have ordered 7,8 and 10k systems with a 30amp input plugs, essentially getting a 5000va for a 10,000va price.  Bottomline, invest in your electrical system if you need these units. 

3) One of the worst calls i get is from people that have 10kva systems and want to upgrade.   They have probably already invested about $4000 in a 10kva ups system (more if it was new), with the unit, some battery packs and the 50amp electrical.  Once you goto the next step of 16kva, the unit, battery packs, and electrical system becomes obsolete.  Plus the 16kva is an expensive step up anyway.   Bottomline, if your panel needs 10kva now, consider using a Symmetra format.  Their components are modular and can grow with you, up to to that 16kva size.

October 25, 2010

When you need Online UPSes

I have noticed a uptick on requests for Online or double conversion UPSes.  So below is a quick primer on what it really means and why you probably dont need one

  • WHAT is it -  Online UPS is a UPS technology or approach to handling how the UPS acts during an event. Regular UPS technology (called line interactive) sense a loss in power and switch to battery power.  This switch happens in 5 milliseconds.  Online UPSes are essentially always using battery power to operate so they never "switch" power.  Further, while regular UPSes can take some "dirty" power before switching over to clean battery power, Online is always providing clean power.   According to Wikipedia Online UPSes main advantage is UPS is its ability to provide an electrical firewall between the incoming utility power and sensitive electronic equipment.  Bottomline, Online UPS are better, but are more expensive. ($439 v. $595)
  •   v. 

  • WHY you DON'T need it  - Almost everything electric is designed to work on our dirty electrical power grid. So if you just want your stuff to work, Online's super clean power really isnt needed.  Further, the 5ms switchover is more than fast enough to keep your equipment humming.  As for surge protection, both systems are pretty pathetic. Its best to get a panel mounted unit as I dont know if that "firewall" can really hold up to a doozy.
  • Why you MIGHT need it - If having a clean sine wave waveform is important, such as in instrumentation or equipment designed for the lab, then its worth it.  Also if you have a backup generator, its best to go with a Online UPS because you really need the firewall with the atrocious power those generators put out.
If you need one, my store has a page for them

October 24, 2010

Best Technical Blog Posts (de facto FAQs)

What are the Important Specs in comparing UPS units

This week a customer sent me a spec page for a UPS brand I had never heard of  (ProVar 5000, or something).  While spec pages have hundreds of features, there are 4 to concentrate on


UPS Technology  -  Today there a 2 types, Line Interactive or Online/Double Conversion.  Online provides the cleanest power and is generally a lot more money.  If the existing spec is Online, its only fair to compare a similar model.  But it is often over requested.


VA/Watts - These are the UPS's electrical capacity.  The VA is often part of the model number and headline spec.  The watts can be 90%, 80% or 70% of that value depending on the units Efficiency.  So, if someone asks for a high efficiency 2200va capacity unit, I will probably spec a 3000va, to get their desired watts just because upgrading to a high efficiency unit is more than upgrading the VA.

Voltage - Tthis is where the spec pages can get you in trouble.  120volt is simple, but higher voltages are much more complex.  There is big difference between Voltage Range and Nominal Voltage.  Ignore the Voltage Range on the spec. UPSes are pre-set to accept 208, 220, 230, and/or 240v.   A 208v system wont  work on 230v and vice versa.  Also, UPSes cant normally change the power.  If you want 230v output and have only 208v at your building, you can't buy a 230volt UPS.  Nearly every commercial building in the US has 208volt.  Rarely would you have 240 or anything else.   Look at my last post about how we have managed the different types


Plugs and Ports -  All input plugs can be changed to match your needs.  The backplate or output receptacles can generally be changed as needed.  So the only port that is important, is the XL or Extended Run port.  Nearly every unit (except those made by APC) has a port to add extra battery packs to to add runtime. Like the Online spec, its important to make sure customers know they are usually paying 10-25% more for this feature.


As for the remaining specs, most aren't critical and usually match among manufacturers.  Frequency, Crest factor, BTus, Environmental, Surge Protection, Wave form, are all about the same for a given UPS size and type.

Two other factors, physical size and runtime, usually can be handled once a particular model has been chosen.      Smaller units usually cost more, and runtime is completely dependent on battery size.  

October 13, 2010

Random APC Part of the month III

As I review an international brochure from APC, I notice some curious new APC UPSes that I have never seen.
This class of Online UPS is called the the Smart UPS RCs

They are just like the SURT line, but these are rated for "Harsh Environment"

They are a 4U rack tower, have about twice the runtime as the regular 3000va SURT300XLI unit,(393ig3) but are rated for upto 50C and down to -20C.  They also curiously have Dataline surge suppression, which is more a Back-UPS product feature.

Presenting the SRC3000XLI  ...


Its for sale at the Brazilian online store TechClube.. which sounds more like an 80s dance place.

October 7, 2010

Why is Powerware the best?

As I have mentioned before, Powerware makes the best UPSes today (2-10kva).

Many people have strong opinions about their brand, but here is my reasoning:

  • IBM units are rebranded Powerware units.  IBM customers pay a premium for the best servers and want the best UPS, IBM couldnt take APC's failures and down market line so changed in 2009.
  • Powerware ships Genesis/Yuasa High Rate batteries in their 9125 line, APC uses junky BB batts on the equivalent model which suggests Powerware doesnt cheapen its components and cares about quality, not always price
  • As electricians, Powerware was always spec'd and installed on new construction projects suggesting engineers respect the Powerware line.
  • Components on Powerware are heavy duty.  Screws, handles, boxes, etc are seem to be better made
So if thats the case, why are Powerware units cheaper on your site?  The simple fact is that APC has better brand recognition to my customers and your demand sets my prices. 

But those in the know, buy up my Powerware double conversion 3000va 2U PW9125 units and laugh at the thought of paying $200 more for APC's version.  

vs 

September 26, 2010

Backplate Options for 2U and 3U units

I have noticed that I have confused a few people with the various backplates on various units.  My listings may show one backplate in the photo, another in the description and a 3rd type that I might ship you.  This is most common on the 202x, 302x and 303x units.

APC works this out by calling the same unit different model numbers depending on the backplate.  Look at the SUA2200RM2U (my 202b)  here and then the SUA2200R2X147 (was my 202q).

So, in order to clear this up, I will redo my product pages to show the most common backplate.  Then I will feature in the listings alternative backplates.

For now look at my backplate page and learn about the options

For the record here are the now official plates

Does the 208v 3000va UPS have more power than the 120volt version

APC recommends high voltage for your UPS and server room, but not because its more powerful



3000va at 120volt [303b] or 208v [383b], is still 3000va... VA is volt-amps.  So the 208volt just takes less amps to get that VA.  You cant plug more stuff into it.

The difference is important when your consumption gets very large.   10 racks taking 3000va each at 120volt suggests 250amps (30000/120) versus 144 amps for 208.

That large of a difference in amperage effects your electrical system.  Services, Panels, and Neutrals are all sized based on amperage.  Your electrician will make alot of money if you keep your UPSes at 120v with any sizable load.  

We recommend going to 208v if your total load is over 5000va.  And if its over 30,000va then go to a 3phase UPS.

September 25, 2010

AGM GEL VRLA SLA... More Battery Questions

I got a call from a customer wanting a 12volt 12ah "gel" battery, and I kinda of stumbled in explaining whether we have one.

The short answer is and should have been... YES   its here (b12)

But, I chose to make it more complicated... Our batteries belong the family called.  VRLA.  Which is Valve Regulated Lead Acid.  These Sealed Lead Acid (SLA) batteries are contrasted with Vented, Flooded or Wet batteries.  Your car battery is a Vented/Wet/Flooded battery.


But within the VRLA family there are 2 species, AGM and Gel Cell.  Our Powersonic batts are AGM (meaning Absorbed Glass Mat). The electrolyte is not a gel but is a liquid in such a small proportion as only to keep the internal mats within the battery damp.   Real Gel Cels dont use any liquid, but rather a gel paste.

It turns out, Gel Cels are more expensive and discharge slowly  (not good for UPSes) and require a proper recharge regiment (also not good for UPSes), plus they tend to be more expensive and create less power per lb.  Finally according to the guys at BatteryStuff.com, "gel" means to most people AGM VRLA, since AGM outsell Gel 100 to 1.   Even Wikipedia has a VRLA AGM listed incorrectly as a "gel battery"

Look how similar the two types of VRLA batts are


Dream Rack.. visualized

Here is the drawing if I could re-do my server rack system.


  1. UPS : 5000va 208v APC XL UPS -- Great value, includes 120v outlets, Extended run option and decent runtime.
  2. Battery Pack 3U -- Adds another 1hour to my runtime
  3. APC PDU Model AP7541 -- connects to 30amp receptacle in UPS and outputs those C13 and C19 ports for computers and power supplies  (we dont sell these)
  4. Extension Cable -- Maybe you dont need it, but being able to have the entire rack powered by a nearby receptacle or generator in a pinch is critical for use.  We would just toss the extra cable on top of the rack
  5. Surge Suppressors  -  We use the IT Protector brand, its really the only one to trust
  6. Flood Stick light - When the power goes down its nice to have a light that can't walk away.  The LED type wont drain the UPS very much.

Planning your Dream Rack

Since I have installed and repaired many UPSes in server racks over the years, here are some of my design points if you have the opportunity to create a dream server rack.


  • Have the UPS Receptacle mounted on the ceiling or the floor...  keep this important cord away from everything else
  • Avoid having a UPS on rack 1 power stuff on rack 2... the wiring gets complicated.  
  • Dont go crazy with this double double redundancy... most equipment has 2 power supplies.  Many people buy 2 UPSes and cross patch each power supply.   While power supplies do fail, when UPSes fail, they normally let regular power pass through.   It looks cool in the brochure, but its really unnecessary.  Use the money to buy a surge suppressor
  • Buy a panel mount surge suppressor... They cost less than a UPS and honestly do a lot more for your power issues.  Get one for your main panel and your server panel, Please
  • Dont mount the UPS on the top of the rack... one day you will need to change the batteries

September 22, 2010

Generations of SmartUPS

With GreenlightUPS now offering the first FIFTH generation of APC SmartUPS, the SMT2200 [200v], I thought I might share with you the previous generations.  Here is the evolution of the low power rack mount unit and store links.

  • Gen 1 - 1990? - SmartUPS 1250va (AP1250RM)
  • Gen 2 - 1995? - SmartUPS 1400va (SU1400RMNET)   ... 403
  • Gen 3 - 2000 - SmartUPS 1400va 2U (SU1400RM2U)  ... 402
  • Gen 4 - 2004 - SmartUPS SUA 1500va 2U (SUA1500RM2U)  ... 402b
  • Gen 5 - 2010 - SmartUPS SM 1500va 2U (SMX1500RM2U)  ... 412v

September 20, 2010

Bob's Best Bets for your UPS needs Rackmount VALUE

Here is my advice for your best value UPS units.  These units deliver all the benefits of the newer UPS units at a fraction of the price.  They come with a 1 year warranty on the unit and 2 years on the batteries if bought in our eStore or over the phone.

  • Small Server group - 1400va - 120v:  APC 1400va 2U in Black  (402c) - $239  ... this unit has the same look as the newer 1440va (402b called a 1500 for some reason) at $50 cheaper.
  • Larger Service group - 3000va - 120v:  APC 3000va 5U in Beige (315) - $429  ...this is just $10 more than the 3u (303), but has 30% more battery life and and Extended run port.
  • High Voltage small - 3000va - 208v:  APC 3000va 3U in Black (383b) - $449  ... better built and cheaper than its 2U cousin (382b) it also has two 120volt outlets which help.
  • High Voltage large - 5000va - 208v:  APC 5000va 5U in Beige (585) - $939  ... a solid workhorse, this unit offers generous battery time and unlike its newer version (585AB), keeps the 120volt convenience outlets

September 14, 2010

New High Voltage Keys for Snips

As per our previous post about the 4 types of high voltage UPS systems, we have changed our product thumbnails (or snips) to show their type of high voltage handling
These refer to (from left to right): 208volt ONLY; 208v or 240v;  220,230,240v; and universal 200-240v.

Here is the old and new snip for IBM's 3000va 2U (392ibm)
 is now  

September 13, 2010

230volt ... and other High voltage systems

There are 4 different ways that UPSes are designed to handle "high voltage"

The first is 208volt only.  This is the most common type of high voltage system, since nearly all server rooms in commercial facilities have this power pre-wired.  The UPSes input this 208v and then output 208v.

The second is 220,230,240v.  These are primariliy for international use.  UPSes using this power format nearly always have IEC type plugs and ports.   Most of the units are auto-sensing for that range.  Unfortunately they do not output 208v.  If you plug these into 208volt, they will output 220,230 or 240v.  So dont buy these if you have 208volt power.

The third type is 208/240v.  Here the UPS can be configured to accept 208v or 240v.  As I mentioned, 208v is common high voltage for commercial facilities, but 240volt is common high voltage in non commercial facilities and in your home (think your dryer).  Most newer APC units are setup 208/240volt.  In these units, the plugs and ports are NEMA twistlocks.

The final type is "universal high voltage."  In these systems, 208v, 220, 230, 240 are accepted.  The UPS auto-senses the voltage.  This format is found in most Tripplite and Powerware systems.

None of these systems step up or step down the power... they output the same as the input.

Below lists some common units for each type.

September 8, 2010

Mea Culpa Dixi... APC's inflated specs, which fooled me too.

Most of time APC's numbering system makes sense.  A SmartUPS 3000 is 3000va, A SmartUPS 5000 is 5000va, however a SmartUPS 1500 is NOT a 1500va unit.

When APC rolled out the black 3rd generation SUA upses, they upgraded our popular SmartUPS 1400 2U rackmount to a "SmartUPS 1500" (SUA1500RM2U)  Yet in actuality, its a SmartUPS 1440.   I've been wrong for years.

So when people call demanding the newer 1500, I will remind them its just a black 1400 with a squidgen more power which I charge at least $50 more dollars for.

Anyway, still the best bet is that 1400 2U (402), but if you want you can get the black Dell branded 1400, (402c) for just a bit more.  

Anyway of you really want the "1500", its here.  But if you want a real 1500va, BestPower makes a great one.

September 5, 2010

Random APC Part of the month II

Even sillier than the the Serial cable surge suppressor is the APC AP9324... Alarm Beacon.


Part of the NetBotz series of products, this alarm beacon will "Quickly notify personnel of critical situations with a visible alarm signal"


Mercifully, it does not have an alarm or buzzer.  But in a pinch it can be turn your server room into a rave den.  Obviously people like this item, as its offered by hundreds of suppliers and is actually ranked 40,000 or so in electronics at Amazon.

September Transformer Clearance

While I have written that Stepdown transformers aren't really needed anymore, there are some applications where its so much easier to have 120volt outlets.

So for the rest of September most of our transformers are 33% off.

Beige 5kva 2U - XF52U - normally $275 >>NOW $183.75
Black 5kva 2U - XF52UB - normally $299 >>NOW $200.33
Black Isolation 5kva 3U - XF52ISOB - normally $455 >>NOW $304.85

September 3, 2010

The best 3000va 120v Rack mount Units

Our most popular type of UPS is the 3kva APC rackmount.  However, we offer at least 9 models meeting those specs.  They range from $409 for the 3U workhorse (303) to the super premium double conversion RT model (313g3).

For your reference, we have made a special table that allows you to sort by relative price, my rating and rack thickness.

The highest rated is the 3U workhorse (303) because its great value, good form factor, price and quality.   The lowest rated is the thin 2U 302b which has heat problems, but is still a very popular seller.   Most of the newer units (310b) and (333B) get low rates not because of quality but because of their much higher cost relative to what you get.   The highest rated unit that is expandable (XL) is the 315.

See the whole table here

September 1, 2010

Full Line of APC Symmetras

GreenlightUPS has a full line of the powerful modular APC Symmetras.

We have the classic SY Masterframe 16kva (SY16), Small PM 6kva rack mounts (SYPM6), Workhorse LX 8kva towers (SYLX8), and the awesome 3phase PX 80kva (SYPX80) systems

These systems offer great flexibility for server and equipment rooms.