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Failed US-24-500W, 13 months of use, repair options?

Any commonly failed components I should be aware of or tips for repair on a 24 port 500W Unifi switch?  I gently used it in a power protected climate controlled lab for 13 months and found it failed this morning.  It provided POE on a single port and was connected only to a USG4 and an AC AP (Unifi) - plus a few non-POE devices.  As these are out of stock or priced somewhat higher than usual my goal would be to repair this unit if at all possible.  I should note I ordered the 250W unit from Amazon but was shipped the 500W, I only ever needed the 250W and it is that model I'm not finding at one of the few vendors our 'corporate' ordering system allows us to order from.  

 

I suspect the PS as I'm not measuring anything on the 48V or 24V connectors on the daughterboard.  Unrelated, but I believe it failed within minutes of the controller upgrading to 5.05RC (no firmware update).  I remotely upgraded and then DCed, the switch was up at the time.

 

It looks like 24VDC is also supplied via CON2(+24VB) - if so I should think I could at least bring the logic side up if I provide it with clean power there - but I'm no electrician.  Given it is a few days out of warranty the unit is landfill bound unless I can fix so I'm open to try anything.  

 

Any help would be appreciated!

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Re: Failed US-24-500W, 13 months of use, repair options?


@ahpsi wrote:

Any commonly failed components I should be aware of or tips for repair on a 24 port 500W Unifi switch?  I gently used it in a power protected climate controlled lab for 13 months and found it failed this morning.  It provided POE on a single port and was connected only to a USG4 and an AC AP (Unifi) - plus a few non-POE devices.  As these are out of stock or priced somewhat higher than usual my goal would be to repair this unit if at all possible.  I should note I ordered the 250W unit from Amazon but was shipped the 500W, I only ever needed the 250W and it is that model I'm not finding at one of the few vendors our 'corporate' ordering system allows us to order from.  

 

I suspect the PS as I'm not measuring anything on the 48V or 24V connectors on the daughterboard.  Unrelated, but I believe it failed within minutes of the controller upgrading to 5.05RC (no firmware update).  I remotely upgraded and then DCed, the switch was up at the time.

 

It looks like 24VDC is also supplied via CON2(+24VB) - if so I should think I could at least bring the logic side up if I provide it with clean power there - but I'm no electrician.  Given it is a few days out of warranty the unit is landfill bound unless I can fix so I'm open to try anything.  

 

Any help would be appreciated!


If you can't fix it, don't junk it, I would gladly pay for the shipping to have this unit with the intention of NOT repairing it.

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Re: Failed US-24-500W, 13 months of use, repair options?

Smart idea! Sell it on eBay as an "as is" unit. jajajajaja
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Re: Failed US-24-500W, 13 months of use, repair options?


@Magbis wrote:
Smart idea! Sell it on eBay as an "as is" unit. jajajajaja

@Magbis, was actually thinking about dipping it in liquid nitrogen and hitting it with a sledge hammer... Man Happy

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Re: Failed US-24-500W, 13 months of use, repair options?

Do it then YouTube or you didn't do it.
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Re: Failed US-24-500W, 13 months of use, repair options?

^ +1
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Re: Failed US-24-500W, 13 months of use, repair options?

@DStahl@Magbis, that is the plan!  I have two older cisco WAPs that are going to get it first!

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Re: Failed US-24-500W, 13 months of use, repair options?


@ahpsi wrote:

 

It looks like 24VDC is also supplied via CON2(+24VB) - if so I should think I could at least bring the logic side up if I provide it with clean power there - but I'm no electrician. 

 

 Find a TV/Electronic repair shop in your neighborhood and give it a try.... if you can find one Out

 

Sometimes will cost you more to fix the device that to buy a new one.

 

Regards,

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Re: Failed US-24-500W, 13 months of use, repair options?

If I can't repair I'll send it to you 

 

 

 

 

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Re: Failed US-24-500W, 13 months of use, repair options?

@ahpsi, if you end up shipping it to me, I promise to freeze it, shoot it, and beat it up real good and put it on the YouTube machine (http://www.youtube.com/williehowe)!

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Re: Failed US-24-500W, 13 months of use, repair options?

No offense intended - but I'm really trying/hoping to fix it!

 

One hope emerges - closer inspection of the board reveals a fried resistor - 0.27 Ohms 5% tolerance, looks to be one watt?  Don't have one here and I'm told it's "non-standard" - but it's a 25 cent part.

 

I can get the board to start to boot when I give it 24VDC - but it doesn't complete and the NIC ports don't light up.  

 

UBNT - is it expected the switch wouldn't complete the boot process if the POE daughterboard was not supplied with 26 and 56 VDC?  I've also tried booting without the daughterboard installed, same result.  Is it likely the mainboard was affected too or is there hope?

 

Thank you!

 

2016-06-01 10.38.39.jpg
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Re: Failed US-24-500W, 13 months of use, repair options?

fried resistors are normally caused from over current, or over voltage that causes excess current = more current than they can handle was flowing through it.  

 

The resistor is not the reason why the psu died. It was just there doing it's job " in most cases" 

 

I would expect to find a blown voltage regulator , shorted transformer , who knows what else that is also bad. Who knows what else could be blown up in there. 

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Re: Failed US-24-500W, 13 months of use, repair options?

From the picture the resistors look ok, is the burn trace on the pcb that is not normal.

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Re: Failed US-24-500W, 13 months of use, repair options?

I'll take another look tomorrow.  I did take a pic of the whole PS but don't remember seeing anything out of the ordinary aside from the resistor.  I actually realized after looking at the logs that I was near it when the resistor failed and heard it pop - it was quite loud - but thought it was a tool falling off a table.

 

I removed the board from the tray and inspected the bottom but did not see any burnt traces and there wasn't the typical 'burnt' odor in the case.  My only remaining concern would be is the mainboard good or is the atypical boot I see when providing it with only 24 VDC an indication it too has failed?

 

20160601_130626.jpg
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Re: Failed US-24-500W, 13 months of use, repair options?

Can you hear the crowd chanting... "Shoot it!  Shoot it!  Shoot it!" Man Happy  Really I hope you can get it fixed.

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Re: Failed US-24-500W, 13 months of use, repair options?

The resistor look to good for a blown one.

 

20160601_130626_b.jpg

 

Check this component wrap in shrink-wrap and attached with the screw ? Power regulator maybe.

 

Have fun Cheers2

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Re: Failed US-24-500W, 13 months of use, repair options?

I agree it does look good from the top.  I missed it because of that but the bottom shows it a bit better:

 

badres.jpg
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Re: Failed US-24-500W, 13 months of use, repair options?

Just a resistor not big deal , the question is how/why that happen.

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Re: Failed US-24-500W, 13 months of use, repair options?

I'm optimistic if I either repair the PS or can source a replacement the switch may yet function.

 

This unit does not have the console port on the back but it does have four pins on the mainboard labelled G R T G which I took to be a TTL port.  I connected it to a TTL > RS232 adapter and get the following:

 

U-Boot usw-v1.1.2.106-gaa988b93 (Jan 11 2016 - 14:27:44)

DEV ID= 0000db56
SKU ID = 0x8344
DDR type: DDR3
MEMC 0 DDR speed = 667MHz
Validate Shmoo parameters stored in flash ..... OK
Press Ctrl-C to run Shmoo ..... skipped
Restoring Shmoo parameters from flash ..... done
Running simple memory test ..... OK
DDR Tune Completed
DRAM:  256 MiB
WARNING: Caches not enabled
membase 0x8000000 memlimit 0x10000000
Done PCI initialization
In:    serial
Out:   serial
Err:   serial
Unlocking L2 Cache ...Done
arm_clk=400MHz, axi_clk=200MHz, apb_clk=50MHz, arm_periph_clk=200MHz
Disabling outer cache
Net:   Board Net Initialization Failed
No ethernet found.
Hit any key to stop autoboot:  0
ubnt_bootsel_init: bootsel magic=a34de82b, bootsel = 0
UBNT application initialized
Boot partition selected = 0
Loading Kernel Image @ 1000000, size = 15728640
Verifying 'kernel0' parition:OK
## Booting kernel from Legacy Image at 01000000 ...
   Image Name:   Ubiquiti 3.7.4.4945
   Image Type:   ARM Linux Kernel Image (uncompressed)
   Data Size:    13918628 Bytes = 13.3 MiB
   Load Address: 00018000
   Entry Point:  00018000
   Verifying Checksum ... OK
   Loading Kernel Image ... OK
OK
boot_prep_linux commandline: console=ttyS0,115200 mem=128M@0x0 mem=128M@0x68000000 mtdparts=spi1.0:768k(u-boot),64k(u-boot-env),64k(shmoo),15360k(kernel0),15424k(kernel1),1024k(cfg),64k(EEPROM) ubntbootid=0

Starting kernel ...

Disabling outer cache
[    0.000000] Booting Linux on physical CPU 0
[    0.000000] Linux version 3.6.5 (build-unifi@t630-builder) (gcc version 4.7.2 (GCC) ) #1 SMP Tue May 24 19:31:07 PDT 2016
[    0.000000] CPU: ARMv7 Processor [414fc091] revision 1 (ARMv7), cr=10c53c7d
[    0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing instruction cache
[    0.000000] Machine: Broadcom iProc
[    0.000000] Memory policy: ECC disabled, Data cache writealloc
[    0.000000] BUG: mapping for 0x18000000 at 0xf0000000 out of vmalloc space
[    0.000000] BUG: mapping for 0x19000000 at 0xf1000000 out of vmalloc space
[    0.000000] PERCPU: Embedded 7 pages/cpu @c1b7a000 s6272 r8192 d14208 u32768
[    0.000000] Built 1 zonelists in Zone order, mobility grouping on.  Total pages: 61952
[    0.000000] Kernel command line: console=ttyS0,115200 mem=128M@0x0 mem=128M@0x68000000 mtdparts=spi1.0:768k(u-boot),64k(u-boot-env),64k(shmoo),15360k(kernel0),15424k(kernel1),1024k(cfg),64k(EEPROM) ubntbootid=0 ubootver=usw-v1.1.2.106-gaa988b93
[    0.000000] PID hash table entries: 512 (order: -1, 2048 bytes)
[    0.000000] Dentry cache hash table entries: 16384 (order: 4, 65536 bytes)
[    0.000000] Inode-cache hash table entries: 8192 (order: 3, 32768 bytes)
[    0.000000] Memory: 128MB 128MB = 256MB total
[    0.000000] Memory: 246228k/246228k available, 15916k reserved, 131072K highmem
[    0.000000] Virtual kernel memory layout:
[    0.000000]     vector  : 0xffff0000 - 0xffff1000   (   4 kB)
[    0.000000]     fixmap  : 0xfff00000 - 0xfffe0000   ( 896 kB)
[    0.000000]     vmalloc : 0xc8800000 - 0xf0000000   ( 632 MB)
[    0.000000]     lowmem  : 0xc0000000 - 0xc8000000   ( 128 MB)
[    0.000000]     pkmap   : 0xbfe00000 - 0xc0000000   (   2 MB)
[    0.000000]     modules : 0xbf000000 - 0xbfe00000   (  14 MB)
[    0.000000]       .text : 0xc0018000 - 0xc0311f5c   (3048 kB)
[    0.000000]       .init : 0xc0312000 - 0xc0d35880   (10383 kB)
[    0.000000]       .data : 0xc0d36000 - 0xc0d5e180   ( 161 kB)
[    0.000000]        .bss : 0xc0d5e1a4 - 0xc0d70658   (  74 kB)
[    0.000000] SLUB: Genslabs=11, HWalign=64, Order=0-3, MinObjects=0, CPUs=1, Nodes=1
[    0.000000] Hierarchical RCU implementation.
[    0.000000]  RCU restricting CPUs from NR_CPUS=4 to nr_cpu_ids=1.
[    0.000000] NR_IRQS:292
[    0.000000] sched_clock: 32 bits at 100 Hz, resolution 10000000ns, wraps every 4294967286ms
[    0.010000] Calibrating delay loop... 795.44 BogoMIPS (lpj=3977216)
[    0.050000] pid_max: default: 4096 minimum: 301
[    0.050000] Mount-cache hash table entries: 512
[    0.050000] CPU: Testing write buffer coherency: ok
[    0.050000] CPU0: thread -1, cpu 0, socket 0, mpidr 80000000
[    0.050000] Setting up static identity map for 0x2527f0 - 0x252848
[    0.050000] L310 cache controller enabled
[    0.050000] l2x0: 8 ways, CACHE_ID 0x410000c9, AUX_CTRL 0x0a120000, Cache size: 131072 B
[    0.050000] Brought up 1 CPUs
[    0.050000] SMP: Total of 1 processors activated (795.44 BogoMIPS).
[    0.050000] devtmpfs: initialized
[    0.060000] NET: Registered protocol family 16
[    0.060000] DMA: preallocated 256 KiB pool for atomic coherent allocations
[    0.060000] GENPLL[5] mdiv=40 rate=2000000000
[    0.060000] Sel=1 Ovr=1 Div=48
[    0.060000] UART clock rate 50000000
[    0.080000] bio: create slab <bio-0> at 0
[    0.080000] Switching to clocksource iproc_gtimer
[    0.080000] NET: Registered protocol family 2
[    0.090000] TCP established hash table entries: 4096 (order: 3, 32768 bytes)
[    0.090000] TCP bind hash table entries: 4096 (order: 3, 32768 bytes)
[    0.090000] TCP: Hash tables configured (established 4096 bind 4096)
[    0.090000] TCP: reno registered
[    0.090000] UDP hash table entries: 128 (order: 0, 4096 bytes)
[    0.090000] UDP-Lite hash table entries: 128 (order: 0, 4096 bytes)
[    0.090000] NET: Registered protocol family 1
[   13.370000] pm_init: Initializing Power Management ....
[   13.370000] iproc gpiochip add GPIOA
[   13.370000] GPIOA:ioaddr f0000060
[   13.370000] GPIOA:intr_ioaddr f0000000 dmu_ioaddr   (null)
[   13.620000] PCIE0: LINKSTA reg 0xbe val 0x1001
[   13.620000] reg[0xac]=0x10, reg[0xae]=0x42, reg[0xb0]=0x8000, reg[0xb4]=0x2c10, reg[0xb6]=0x10, reg[0xb8]=0x5c12, reg[0xba]=0x65, reg[0xbe]=0x1001, reg[0xc6]=0x40, reg[0xca]=0x1, reg[0xd0]=0x1f, reg[0xd2]=0x8, reg[0xdc]=0x2, PCIE0 link=0
[   13.970000] PCIe port 1 in End-Point mode - ignored
[   13.970000] Registering iproc_pmu_device
[   13.970000] bounce pool size: 64 pages
[   13.990000] squashfs: version 4.0 (2009/01/31) Phillip Lougher
[   13.990000] jffs2: version 2.2. (NAND) © 2001-2006 Red Hat, Inc.
[   13.990000] msgmni has been set to 224
[   13.990000] Block layer SCSI generic (bsg) driver version 0.4 loaded (major 254)
[   13.990000] io scheduler noop registered
[   13.990000] io scheduler deadline registered (default)
[   13.990000] io scheduler cfq registered
[   13.990000] Serial: 8250/16550 driver, 2 ports, IRQ sharing enabled
[   13.990000] serial8250.0: ttyS0 at MMIO 0x18000400 (irq = 123) is a 16550A
[   14.440000] console [ttyS0] enabled
[   14.450000] serial8250.0: ttyS1 at MMIO 0x18000300 (irq = 123) is a 16550A
[   14.470000] brd: module loaded
[   14.490000] loop: module loaded
[   14.490000] nbd: registered device at major 43
[   14.520000] tun: Universal TUN/TAP device driver, 1.6
[   14.520000] tun: (C) 1999-2004 Max Krasnyansky <maxk@qualcomm.com>
[   14.530000] TCP: cubic registered
[   14.540000] NET: Registered protocol family 10
[   14.540000] sit: IPv6 over IPv4 tunneling driver
[   14.550000] NET: Registered protocol family 17
[   14.560000] 8021q: 802.1Q VLAN Support v1.8
[   14.560000] GENPLL[5] mdiv=40 rate=2000000000
[   14.570000] qspi_iproc qspi_iproc.1: 1-lane output, 3-byte address
[   14.570000] m25p80 spi1.0: found mx25l25635e, expected m25p80
[   14.580000] m25p80 spi1.0: mx25l25635e (32768 Kbytes)
[   14.580000] 7 cmdlinepart partitions found on MTD device spi1.0
[   14.590000] Creating 7 MTD partitions on "spi1.0":
[   14.590000] 0x000000000000-0x0000000c0000 : "u-boot"
[   14.600000] 0x0000000c0000-0x0000000d0000 : "u-boot-env"
[   14.610000] 0x0000000d0000-0x0000000e0000 : "shmoo"
[   14.620000] 0x0000000e0000-0x000000fe0000 : "kernel0"
[   14.620000] 0x000000fe0000-0x000001ef0000 : "kernel1"
[   14.630000] 0x000001ef0000-0x000001ff0000 : "cfg"
[   14.640000] 0x000001ff0000-0x000002000000 : "EEPROM"
[   14.670000] Freeing init memory: 10380K
[   14.710000] ubnthal: module license 'Proprietary' taints kernel.
[   14.710000] Disabling lock debugging due to kernel taint
[   14.820000] ubnthal: Ubiquiti USW-24P-500
[   14.840000] gpiodev: (reset_timeout=3 factory_countdown=300000)
...running /sbin/init
init started: BusyBox v1.19.4 (2016-05-24 19:24:14 PDT)
+ exec
Restoring EEPROM data from ubnthal
MAC: 04:18:d6:83:14:2e
SyncDB Running...
Validating the active image /dev/mtd3..."3.7.4.4945"
Validating the backup image /dev/mtd4..."3.7.3.4925"
DMA pool size: 4194304
AXI unit 0: Dev 0x8344, Rev 0x01, Chip BCM53344_A0, Driver BCM56150_A0
SOC unit 0 attac[   31.470000] Received 2 PSE boards registered with pid 735
hed to PCI device BCM53344_A0


<10> Dec 31 19:00:42 0.0.0.0-1 UBNT_POE[63042780]: ubnt_poe_common.c(4909) 1 %% PSE init failed 0x003f, retry 1

<10> Dec 31 19:00:45 0.0.0.0-1 UBNT_POE[63042780]: ubnt_poe_common.c(4909) 2 %% PSE init failed 0x003f, retry 2

<10> Dec 31 19:00:47 0.0.0.0-1 UBNT_POE[63042780]: ubnt_poe_common.c(4909) 3 %% PSE init failed 0x003f, retry 3

<10> Dec 31 19:00:47 0.0.0.0-1 UBNT_POE[63042780]: ubnt_poe_common.c(3612) 4 %% PoE Initialization failed in Hardware

cnfgrApiCallback: Failed by task 0x3c1f4dc in file ubnt_poe_cnfgr.c line 201.
log_error_code cnfgr_tally.c  199

Switching software SIGSEGV Handler
This build was configured to copy this crash information to
  a file.
+ exec
The system is going down NOW!
Sent SIGTERM to all processes
Sent SIGKILL to all processes
Requesting system reboot
[   51.810000] Disabling non-boot CPUs ...
[   51.810000] Restarting system.

I can see why it reboots - "PSE init failed" - agreed, it's failed.  The board won't be able to initialize the PS until I can give it one.

 

The one that concerns me is

"Net: Board Net Initialization Failed
No ethernet found."

 

Anyone know if this is normal?

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Re: Failed US-24-500W, 13 months of use, repair options?

Base on your full picture look like your PSU have to power circuits(opposite symmetrical), one for local system and one for POE. The blow resistor(R5) is on POE side , if you take a look on the system side(top left) you will see a resistor placeholder(R2) that is not populated. In my opinion I don't think that resistor R5 is the only component that fail or fail by itself , think as fire like radio waves(wireless) , stronger in the center and weaker away from the point of origin.

Base on my opinion, the resistor is not the origin of your problem, the electronic component mark be yellow flash in my previous post is the problem.

 

base on your boot log , the kernel just quilt since teh POE fail. If you are ready to take the risk you can reset the device and up load a fresh firmware.This step will bring your system to defaulter(POE disabled) and you wil see if the system boot

 

Regards,

Do not expect me to reply to this post, I'm not sure that I will be able to find it, thank's to ....