9 replies to this topic

[CCARMINATI]

Hi, I have issues with 5 diferent XTI amps. Before someone asks, amps have been tested outside the rack without any contact with the other amps. The issues I will describe are intermitent and present on some of the amps from time to time or sometimes at all amps at the same time:
1)Amps starts up just fine, but a second before the green light should turn green it turns off (relay clicks before going off).

2)After pressing the power button, the amps screens and input signal leds blink a couple of times like the amp was 'trying to start'; sometimes they do start, other times they shutdown.

As mentioned, it has happened with all, some or none of the amps at any given day.

[joust]

For part 1): My thinking is that there may be an output failure, possibly with the Cequel Tracker fets. It 'feels' like the VCC rails are not equal. The Tracker module permits the amplifier to switch between two rail levels, like on the MA5K series.

For part 2), it may be the bootstrap (KSTART) cap, it may be out of tolerance. You'll have to troubleshoot a little more when the amp is down.

Hope this helps!

Alain

[CCARMINATI]

Thanks Alain, but you really think that it is possible that I have the same issue with 5 diferent amplifiers?

[joust]

It is troublesome! I can't really say for sure, but it is possible. Though, what may all seem as same issue may not at all be related. The sample mode power supply (SMPS) behaves in much the same fashion when an outside fault is detected; Many different detected faults just stops the SMPS from driving on.
You may have to wait until the amp(s) break down before delving further in. Also, get in contact with your local Crown authorized dealer or service center.

(Did you implement the latest firmware updates?)

Alain

[CCARMINATI]

I believe that I am running the latest firmware (1.1.5.6). One thing that I noticed is that the issues wont appear as much on good power scenarios (Like on large and well prepared clubs or when running on a generator). I was able to cause a failed startup (3 out of 5 tries) by connecting one of the amps to an ungrounded power cord (5 out 5 good startups at the same amp on grounded cord). Could a grounding issue be the problem? I also noticed that when the rack is not connected to a grounded AC, I can get a really nice shock by touching the amps. IS that ok?

[joust]

Latest version with SA3.40 mentions both the 1156 and 2032;

As for ungrounded equipment: PLEASE PLEASE make sure your [rack] system is properly grounded! If you can get shocks, there is now potential of lethal dosage! I have heard of musicians (guitar players) getting shocked through a faulty PA (mics were grounded to the wrong side of the AC supply) and dying on stage! Just beware!

And yes, it is now possible that the electric circuit may be involved in your faults! The grounding may not be an issue: the electrical wiring may be the issue! Of course, the grounding too. Why is the electrical system not grounded?

A possible problem is current starvation from the AC power supply: the SMPS needs at a minimum perhaps 90 to 100VAC of AC power supply voltage; If the outlet doesn't permit the power requirement for the amps then they will get starved out.

Hope this helps!

Alain

[CCARMINATI]

System is grounded. Removed ground just for testing/troubleshooting. Firmware 2032 for XTI amps?

[joust]

If you have a multimeter, you could verify the voltage when the amps fails; Before powering up the amp setup the multimeter as close as possible to the amp's power outlet. Make measurements before and after powering up. I still think it's a power distribution issue.

Version 2.0.3.2 is availble with SA3.4; It may have been made available for the '02 models, my bad.

A.

[danmars]

i have an xti 2000 made in 2006 that wont cummunicate with my pc .it turns on and off on its own when connected to pc. but system architech and band manager both will not detect the device.any thoughts

[joust]

Hello Danmars,

Take a look at the first entry, 'Firmware updates for older XTi amps', located as the first FAQ in the Forum lists. It has an executable to load older XTI firmware. Hope this works!

Hey Carminati, Did you get your grounding and electrical issues resolved?

Alain