10 Replies Latest reply: Jan 25, 2010 10:53 PM by Reid RSS

DIY mod XS 1300 LED : added external batteries with success: update report

Reid Novice
Currently Being Moderated
{color:#0000ff}*Shortcut to the Slide Show, easier than reading all this text.*{color}
*but {color:#ff0000}DO read the texts if you plan to make your UPS run from external battery{color}*{color:#ff0000}.{color}
[http://tinyurl.com/6z4dpy]
(slide show, can be played "slow" and paused at will)

-----
*What:    add an external battery* to a UPS? In my example: it is the Back-UPS 1300 (the LED display model)
Why:       to gain added run time of as much duration as one might like.
The stock battery is a series connected pair of 12v, 9AH.
Adding 18Ah of external 24V will, in theory, more than treble the run time on battery alone.

{color:#ff0000}*WARNING*:{color} any such modification will not only void the manufacturer warranty,
and also pose a serious risk of fire or damage to anyone who does not know how
to solder and fuse and use proper gauge wire, depending on the length of the tether.
The proposed modification of adding external battery is KWYADAWYADI
*(know what you are doing and why you are doing it)*.

IF you do this stunt, APC bears no responsibility for any mishap that may result.
You will be on your own if you explode a battery or burn down your house.

NB: I am not affiilated with APC or any maker or firm; I am only a DIY home user fellow.
THIS is not any sort of "official" or even necessarily "correct" way to go..
...however, this is the plan:

to start: what do =you= think of the dreamy proposition of running your home model UPS






* on battery power for 30 minutes,  or three hours, or twelve hours, or days, even,
* depending on how much external, lead acid gel-cell type battery to add to the system?

Remember: this must be done with soldered connections, full fusing of the external battery,
*and is not to be recommended for casual home users. You must KWY-A-DA-WYADI.*

I will share my own thoughts. This is a project in the making, real time, with a newly purchased XS 1300.
This XS 1300 runs at 14% load on average: my particular home computer plus monitor plus dsl modem.

This load draws, according to the LCD readout, more or less, 110W.

The UPS,  by nature, is a conversion device: in order to produce output AC,
it consumes more power from the battery more than the AC power delivered:
that is to say, there are conversion losses from DC battery current/power processes,
into AC waveform current/power.




Q: what is the Ah capacity of an XS 1300's twin-pack (series connected twelve volt) battery?
*9Ah at* 24V. Not much more than that of lead acid battery can go into a UPS of small form factor.

Note: Someday in the distant future, lithium batteries may make good service for UPS supplies, but I don't see how:
light, energy dense, but with serious drawbacks:




























lithium does not like to be kept at full charge all the time; full charge on float shortens LiPO life...




























*...the very opposite of lead acid battery technology*, which wants a full charge, always, and to be recharged instantly after use, for best lifespan.




























{color:#0000ff}*Lead acid is a mature and time-tested technology*{color}. Lead just happens to be sort of heavy!

__________

The adding-more-battery proposition is not a difficult DIY project,
*but it is {color:#ff0000}DANGEROUS{color} to implement {color:#ff0000}for any careless or inexperienced person{color}.*
















































































* It is SAFE only *if done by a person who knows what he is doing and _why _he is doing it*

























































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































last edited 26 Jan. 2010 by r.w.
  • 1. TIME TEST of the new, unmodified XS 1300: to run a 14% load...for how long?
    Reid Novice
    Currently Being Moderated
    OK. At this moment of writing/posting the bone-stock UPS XS 1300 is unplugged from the house AC.
    *{color:#0000ff}I am writing, running along, on UPS battery power alone.{color}*
    The UPS is running fine on its battery-power-to-AC function. It is outputting 115VAC,
    and the load, due to the115VAC, reduced from 124VAC house power, is now drawing only 90W.
    This is all good, as expected, normal. Let's see how long before it must shut down?

    WARNING: deep cycling any lead acid battery reduces its service life dramatically.
    This is a test and it will not be any favor to the poor little internal batteries,
    now being drained at a good, stiff (though not nearly maximum) rate.

    Rules Inherent of lead acid batteries: the less the current draw, the greater of the
    -rated- Ah capacity can be gained. Ah capacity is normally figured at a LOW
    drain rate. My "test" here is not a low drain rate.
    ALSO: the more times a battery is deep-cycled, the sooner it dies permanently.

    POINT: if we later add external battery (it will be in "parallel" connection),
    then the drain rate of this =much bigger, total battery= is much lower,
    and so we gain a win-win: less punishment on the internal batteries,
    and longer run time. It will also mean much longer re-charge time
    if the proposed-added battery system is inserted to this system.

    {color:#0000ff}The timer is ticking. I am now ten minutes on UPS XS 1300 OEM battery power.
    "estimated time remaining: "41 minutes", says the LED screen.{color}

    Keep in mind that my load is only 90W now at this good, reduced AC voltage of 115V.

    -----testing continuing---- I will add text to this post until the poor thing must shut down.
    I have an external count-down timer in hand, counting down from One Hour....we are now at minute number thirteen...

    -----still running on battery power alone at fifteen minutes from the start of UPS power. The LED says "39 minutes of run time remaining".

    ----Note again, this punishment test is a mild one:
    On battery power, with the output AC reduced by design, to 115 nominal,
    am drawing less than 100W from a machine capable of seven times that number and more..
    but then, it would run hungry (700W, say) equipment for only five minutes or so.

    ----While I pass the time, I will speak about FP&L here in Coconut Grove, Florida:
    bap! the power goes out for a fraction of a second, or up to many hours at a time,
    as when some drunk driver crashes into one of Main Highway's
    old wooden poles set three feet back from the wood-lined roadway.

    -----{color:#0000ff}Now twenty minutes on UPS Battery power. Looking good!{color} It says on the LED: "34 minutes of run time remaining."
    I am just sitting here, impressed by the quite whir of the UPS' internal fan, keeping its conversion electronics cool and comfy.
    This fan, as do the conversion electronics, cost some battery power, but not so very much. 115AC output voltage, holding steady;
    Load: "89W". All is well in UPS land here. These paragraph dashes indicate time intervals between these real-time reports.

    I think I will watch a Youtube video to help pass the time. This will work the graphics card a bit, and cost a bit more of power demand.
    Notes: running the video, playing Youtube at full screen on this Acer 22" monitor, increases the power used, from 90W to about 115W.
    Off to watch more video.

    Mostly though, the reason I got this UPS is to save me from losing long-to-upload video HD uploads to youtube, etc, which takes hours,
    sometimes, over our low speed DSL. If the upload is large and long term, the UPS, if "upgraded" by more battery, will save me much
    grief from Florida Power and Light's too-frequent long-hours blackouts. Mostly, though, the power just blips off for mere seconds.
    We don't have brownouts, but we do get black outs, it seems, if a bird lands on a power line. Brraaaap! (lol).
    Just passing the time....don't mind me. UPS is working great. I simply chatter away.....killing time, just to beat the band.

    -----Screenshots to come shows "x minutes remaining", according to the Powerchute software image. Meanwhile, the UPS LED says "estimated time...18 minutes".
    Load indicator: about 100W. Hint: the battery voltage is naturally, necessarily, gradually falling off, and so the output power voltage, which still reads "115V" is a nominal,
    not an exact reading. No matter. The system runs just as fine as it does on AC house power.

    -----At forty minutes actual UPS run time, the Powershute estimates 6 minutes time remaining and the UPS, itself, estimates 15 minutes.
    Rhetorical question: will the Powerchute shut us down in six minutes? If so, that's alright: the less that we deep-cycle a lead acid battery, the better.
    Better to NOT run any sort of battery down any more than necessary; lead acid loses service lifespan when deep cycled.

    ------Powerchute now says "2 minutes to shutdown, and the UPS LED says "9 minutes".
    {color:#0000ff}We have now been on UPS power for 45 minutes, average load, about 110W, guesstimated.{color}
    If Powerchute (data cord is connected) DOES shut us down in a couple more minutes: fine!
    Let's see the final result shortly. Next posting must be in a new form, for {color:#0000ff}*we are soon to shut down here*.

    {color:#333333}-------{color}*48 minutes* and getting to the thin white line.
    {color}More later....

    R. W.

    Message was edited by Reid, adding blue highlights to the key portions of the text.
  • 2. Re: Discussion thread: pros and cons of adding an external battery
    Reid Novice
    Currently Being Moderated
    Alrighty! The UPS XS 1300 ran my system, as described above, for just over 48 minutes.
    * I pushed that "*post*" button for the previous posting Just In Time, or I would've lost the post-record entirely.

    This Visa/HP computer and the Powershute software are set to:  shut off the monitor, then put the computer into "sleep" mode.
    This it all did.  When I re-plugged in the UPS to the house power, the computer awoke and resumed playing the video I was watching.

    Summary:  ALL WENT WELL.   The run time met my expectation.   The UPS runs quietly when on its battery power mode.
    The run time is adequate for my real-life needs: If I were doing a long-time video upload (can take four hours, some of them,
    then I can easily, if here, set up the Honda 2000ie generator for assured hours of power.

    But what if I were not here?  I would love to have a two or four or six hour run time-potential.

    MY PLAN:  a external, larger capacity gel-cell-type battery; I have found a pair of old but unused "18Ah, 12V" chinese bricks.

    IF they still work, a may gain double or more the present 49 minute run time
    *and so{color:#0000ff} save me from losing video upload attempts longer than the stock{color}*{color:#0000ff}
    OEM in-built battery can provide.{color}

    *See the first posting again?  {color:#ff0000}Note that to apply an external battery safely MUST be done by a competent person.{color}*
    I am a competent person.  But you know, if I err, it will be my own fault, and no blame can be placed except upon myself.

    And if YOU do this trick and get into trouble: burn down your house or make sparks fly or explode a battery: it will be YOUR fault,
    and no fault of mine, and certainly no fault of APC.    KWYADAWYADI  (!!!!)

    That is all for now.  Thank you, APC, for a well-designed and popular unit.

    The LED data screen was what sold me to buy your product at full retail price from the local Best Buy, two days ago.

    I hope it will last for me well, but I do understand:
    ANY modification of ANY OEM product voids not only the maker's warranty,
    but also absolves the maker of any and all responsibility for mishaps that could, come, but will not come, in this test case.

    Heavy wire, good soldered connections, fuses, and.... I will have possibly, nearly two hours of run time.
    If not, then I buy a new pair of about 30AH gell cell batteries.

    More to come,

    Reid Welch

    Message was edited by: Reid to update the data: not using the old, single Optima battery.
    I need 24V of matched 12V cells for outboard use.
  • 3. Re: Discussion thread: pros and cons of adding an external battery
    Reid Novice
    Currently Being Moderated
    ___________________Coming soon:

    {color:#ff0000}*How to splice into heavy wire and SOLDER such thick stuff effectively.*
    How to INSULATE, how to fit cheap, SAFE connectors; how to FUSE.
    Fusing is VITAL. All this will be coming into this post-form,
    with video links if and as needed. {color}

    Meanwhile, here is some basic reading,
    [http://www.batterystuff.com/tutorial_battery.html]
    (very simple, yet comprehensive enough for our needs)
    where to learn more about gell-cell lead acid
    battery characteristics.

    I learned my licks from the e-bike community, where we often would parallel
    many batteries; like-capacities is not required when wiring cells in simple parallel config.

    Trivia: Edison spent years developing his famous nickel-iron alkaline battery.
    Pluses: it could, in series, power electric trucks, cars, cabs, light railway cars.
    It remained in production for more than fifty years. Each large cell, the size of a car battery, but oblong-tall,
    gave only 1.2V, but steadily, no voltage drop until it was fully discharged.
    It remains the most durable, fool-proof, no-memory, charge it at high rate or low rate, battery ever invented.

    I had, once, a delapidated 1916 Detroit Electric. One owner; car in dead storage since 1954.
    When I obtained the car in 1984, I pulled out all the many, large. heavy 1.2V cells Edison Iron Clad cells.
    I topped them all with distilled water. I put them in series connection, and with a simple bridge rectifier
    and ballast circuit of a large light bulb, put them on charge. These wet cells, then seventy years old,
    every one of them came back to full capacity. I had only enough cells to make about 84VDC,
    but that was enough to run the big shop vacuum (universal wound AC/DC motor) for endless hours.
    That was the Edison's sole advantage: a battery that would never be harmed by time or deep discharges!
    In fact, the kindest way to store an Edison cell is to keep it full of its alkline electrolyte, and if in dead storage,
    discharge it totally,and SHORT the plus to minus terminals!

    The Edison battery option for the '16 Detroit Electric, was extraordinarily costly ($800, then!) to make, and bulky
    and it required constant watering of the batteries, which fizz like soda pop while charging.

    {color:#0000ff}*Lead acid gell-cell is the practical battery for UPS products for the foreseeable future.*{color}

    btw....

    Reid is a chatterbox, not an UPS. :D

    Message was edited by: Reid, removing obsolete data and retouching the trivia section
  • 4. Re: Discussion thread and DIY thread: to add an external battery
    Don =SE= Employee
    Currently Being Moderated
    I would just like to point out that although this is a very interesting experiment, APC does not condone or support any of the procedures Reid has listed above. APC also does not support the use of non-APC replacement batteries unless cleary and explicitly listed in device documentation. Please be safe and use all listed cautionary measures in our documentation when using an APC UPS or other unit.
  • 5. WORD to the wise, in red below, and also above
    Reid Novice
    Currently Being Moderated
    {color:#ff6600}*AMEN to Erasmus' words above.*
    Folks, you are on your own if you try this stunt.{color}

    ---

    Have just completed the basic conversion.

    An upload of the DIY photos of this afternoon's work will be ready to show soon.
    Disregard the Optima photos, per se, except they do show how battery capacity is most generally
    determined by weight, though there are other design considerations, deep cycle or starting-engine types
    are all made a bit differently.

    All that I need now is 24V of external battery to put into the system; that will come next,


    and that will come next, for I have found the pair (trio, actually) of 18Ah-when-new, NOS bricks.
    Two are being glued piggyback right now and are on the auto battery charger taking in a few amps.

    Message was edited by: Reid
  • 6. READY TO ADD ON 24V of EXTERNAL BATTERY
    Reid Novice
    Currently Being Moderated
    {color:#0000ff}*HERE IT IS,*{color}
    *[http://tinyurl.com/6z4dpy]*
    a slide show you can play fast, medium or slow, or pause,
    or choose other picture veiwing options, as you like.
    MORE images will be added in the coming days.

    Am hoping the old NOS 18Ah cells still retain some useful capacity.
    If not: off to the store to buy some ca. 30Ah 12V batteries, two of 'em.
  • 7. Battery University.com on SLA batteries: care, prolonging life, etc.
    Reid Novice
    Currently Being Moderated
    [Battery University.com|http://www.batteryuniversity.com/parttwo-35.htm]

    partial quote for convenience:
    {color:#808000}
    How to restore and prolong lead-acid batteries (BU35)

    The sealed lead-acid battery is designed with a low over-voltage potential to prohibit the battery from reaching its gas-generating state during charge. This prevents water depletion of the sealed system. Consequently, these batteries will never get fully charged and some sulfation will develop over time.

    Finding the ideal charge voltage threshold is critical and any level is a compromise. A voltage limit above 2.40 volts per cell produces good battery performance but shortens the service life due to grid corrosion on the positive plate. The corrosion is permanent. A voltage below the 2.40V/cell threshold strains the battery less but the capacity is low and sulfation sets in over time on the negative plate.

    Driven by diverse applications, two sealed lead-acid types have emerged. They are the sealed lead acid (SLA), and the valve regulated lead acid (VRLA). Technically, both batteries are the same. Engineers may argue that the word 'sealed lead acid' is a misnomer because no lead acid battery can be totally sealed.

    The SLA has a typical capacity range of 0.2Ah to 30Ah and powers personal UPS units, local emergency lighting and wheelchairs. The VRLA battery is used for large stationary applications for power backup. We are looking at methods to restore and prolong these two battery systems separately...{color}
  • 8. Re: Battery University.com on SLA batteries: care, prolonging life, etc.
    Reid Novice
    Currently Being Moderated
    Hello all again.

    Have now completed the addition of the twinned external pair of 18AH cells, wired to offer 24V nominal to the Back-UPS.
    Am writing now on battery power. These external batteries are fully three years old, and though they were never used,
    they are not likely to have much capacity left to them.

    Let us see how long I can run on battery power alone? Last time, the test was with OEM-only internal battery.
    The computer and monitor and modem were powered then, just as they are now, by the Back-UPS for an impressive 49 minutes.
    Such punishment (deep cycling) is terrible on a battery's life---but we are doing this test to learn of potential run times; not worried
    that this will drastically reduce battery life span.

    "We" (you are here with me in spirit, so to speak, are at the thirty minute mark now.
    I am uploading the most recent pictures of the conversion to Photobucket.
    Will arrange them into the slide show so you can see how and what I've done to finish this job.

    If I don't get the run time I want (at least an hour), then it is time to replace the 3 year old external cells.
    And that I will do---get a couple of, probably, wet cell batteries of relatively low cost and decent amp hour rating.
    I can use wet cells, for they are not going to be turned on their sides or bumped around.

    Although wet cell lead acid can take higher float voltage (and that gives them higher capacity), they can live well
    on the slightly lower float voltage provided by the UPS, to keep them in good shape for a few years.
    Will decide on whether or not and what kind of battery to get later. Perhaps these two old bricks will serve for now.
    If I only get an hour of run time---they are not worth keeping, hardly, but they do help ease the workload on the internal batteries.

    -----
    It is now one hour on battery. The LED time remaining indicator says "17 minutes remaining".
    We cannot go on that. All that the UPS can sense is battery voltage, which slowly declines.
    From that number, the UPS' computer estimates Time Remaining upon the expected discharge curve
    of their stock 9Ah internal battery. HERE, though, we have trebled the battery capacity (but the new cells are old and not likely to be very good).

    We -could-, at our low drain rate of about 100W, run for three hours or so on 27Ah total, of battery.

    We -could-, disconnect and throw away the internal battery when the day comes that it is worn out.

    We -could- run a Back-UPS solely from a pair of external batteries, even plain old car batteries (but match them exactly! Two new ones, only, please).

    We can do things safely, or..... {color:#ff0000}or ELSE YOU BURN YOUR HOUSE DOWN. {color}

    I am being stern-talking only to ensure that everyone RESPECT the power stored in even a small battery;
    even a flashlight battery can cause an OUCH, hot pocket
    if you have car keys and an AA cell in your pocket together.

    {color:#0000ff}*The Latest Photos Show the Rig as it it RUNNING RIGHT NOW*{color}:
    [http://tinyurl.com/6ao9mc]

    You can slide-show it, or pick out any single picture to read its written text details in full.

    Next report: after this rig runs down and shuts off. We are at one hour and eight minutes....
    upload a small image. Set to turn off the UPS when it thinks that only "five" minutes of time remain.
    WE NEVER run lead acid batteries below about 10.5 minimum. We shut off the drain early, to preserve cycle life.

    Pay no real attention to the screen shot's numbers. They are tailored as if we had only 9Ah of battery

    Have now been running for one hour and twelve minutes. This is good, fully twenty minutes more than OEM brand new stock.
    I may just get excited enough to go buy NEW 30AH batteries, just for the love of the idea of having so much run time.

    YOUR results will be different.. YOUR load may be much higher than my average-on-battery draw of a mere100W AC load.

    One hour and fifteen minutes now. I am gonna go watch Youtube till it shuts down.
    When I return to ths posting form in a while, {color:#ff0000}In RED INK you will learn how long it went, after all.{color}

    Cheers, look for a {color:#ff0000}*RED* {color}PS here soon, that is all.

    Reid Welch
  • 9. Re: Battery University.com on SLA batteries: care, prolonging life, etc.
    Reid Novice
    Currently Being Moderated
    RUN TIME TO SHUT DOWN,
    Back-UPS XS1300
    plus 18Ah of external, 24V battery, NOS neglected cells;
    average AC draw only about 100W:

    _*{color:#ff0000}2 hours and thirty minutes{color}*_

    instead of the same test run with the stock unit, which gave "only" 49 minutes (which was quite sweet in itself)

    :x

    APC! Rocks!

    ______________

    More resource threads. Learn about lead acid batteries:
    [http://www.windsun.com/Batteries/Battery_FAQ.htm]

    partial quote:
    {color:#808000}Lifespan of Batteries

    The lifespan of a deep cycle battery will vary considerably with how it is used, how it is maintained and charged, temperature, and other factors.

    In extreme cases, it can vary to extremes - we have seen L-16's killed in less than a year by severe overcharging,
    and we have a large set of surplus telephone batteries that sees only occasional (5-10 times per year) heavy service that are now over 25 years old.

    We have seen gelled cells destroyed in one day when overcharged with a large automotive charger.

    We have seen golf cart batteries destroyed without ever being used in less than a year because they were left sitting in a hot garage without being charged.

    Even the so-called "dry charged" (where you add acid when you need them) have a shelf life of 18 months at most.

    They are not totally dry - they are actually filled with acid, the plates formed and charged, then the acid is dumped out.

    These are some typical (minimum - maximum) typical expectations for batteries if used in deep cycle service.

    There are so many variables, such as depth of discharge, maintenance, temperature, how often and how deep cycled, etc.
    that it is almost impossible to give a fixed number.


    * Starting: 3-12 months
    * Marine: 1-6 years
    * Golf cart: 2-7 years
    * AGM deep cycle: 4-7 years
    * Gelled deep cycle: 2-5 years
    * Deep cycle (L-16 type etc): 4-8 years
    * Rolls-Surrette premium deep cycle: 7-15 years
    * Industrial deep cycle (Crown and Rolls 4KS series): 10-20+ years
    * Telephone (float): 2-20 years. These are usually special purpose "float service", but often appear on the surplus market as "deep cycle". They can vary considerably, depending on age, usage, care, and type.
    * NiFe (alkaline): 5-35 years
    * NiCad: 1-20 years
    {color}

    Message was edited by: Reid
  • 10. after one year of repeated (bad for batteries) deep cyclings:
    Reid Novice
    Currently Being Moderated
    Well, the external battery-add on described last year, above works fine.

    Often we have power outages here from half a second, to up to six or eight hours,
    several times per year.

    My main want is to avoid a loss of upload of any sort of YT video (that's my hobby).
    The DSL service here is slow.

    The old computer and the 22" LCD monitor draw an indicated 140W or so, on AC power.
    When the line power cuts out, this smart APC product wisely reduces the output voltage:
    good. More run time. I don't have to haul out the old Honda generator, nor interupt a one hour video upload.

    But, having deep cycled the internal pluse external batteries so many times (not a good practice for any lead-acid battery,
    and the external batteries were old to start with,

    have just, tonight "_excised_" the internal "7Ah" (I think they are) paired-12V OEM batteries.

    In their place now, just hooked up: ALL external battery.
    a pair. I think, am not sure, that they are a nominal "12Ah".

    Will make some new images soon, in a few days, and test the system for run time,
    using the APC USP connector cord so the unit can know the voltage drop of the batteries,
    and know when to shut down.
    {color:#ff0000}
    *This is safe ONLY if you know exactly what you're doing, and don't mind the extra bulk.*
    *DO NOT do this mod if you expect to ever need warranty service...you've altered the design.*
    *APC cannot be responsible for home user mods like this.* {color} An error? {color:#ff0000}*You can blow up a battery*
    *or even cause a fire.* {color}

    Images will soon show the new set up.
    {color:#0000ff}Will give it a few days for the new battery pair to settle in,
    and then do ONE full-cycle to see that I get about two hours or so of runtime.
    I just do not know yet the runtime that these "maintenence free", wet cells will give,
    nor how long they will last in service. Time will tell. {color}

    SO much depends on the load,
    the power extracted, at what rate and for how long, when the utility power supply fails.
    And oh, here in Coconut Grove, outages are...like every time it rains or the wind blows
    a branch into a pole, or a drunk driver takes down a utility pole.

    Our streets in this neighborhood go black.
    {color:#0000ff}For real long outages, have a good old _Honda EU2000 ICE generator_, runs indefinitely,
    but _it does not start itself_ However, the{color}{color:#0000ff}

    *UPS XS 1300 provides full time, clean, regulated power,*
    *fine for computer stuff, twenty-four seven.*

    *Great product. No complaints here, ever.*

    *Will soon make a little YT video showing the present set up,*
    *speaking as an amateur who pretty much knows +how to not +destroy his home,*
    I _do_ hope! {color}

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