XTL Multi-head Combined Control Cable Limit?

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JeffFireRadio
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XTL Multi-head Combined Control Cable Limit?

Post by JeffFireRadio »

Greetings. I have a small town city hall that has recently had installed, an XTL2500 as a control station. It is configured as a dual head unit in order to control it from two separate parts of the building. Each head has a dedicated Astron power supply for 12vdc power. The radio ran fine on the bench with the factory dual 17' control cables. Our MSS ran two-131 foot control cables during the installation (through interior ceiling conduits) and upon power up, it no longer operates correctly and displays a variety of the standard error codes. Cables have been checked and are good. Back on the bench again, it operates correctly with two-17 footers. Apparently two-131 foot control cables at the same time have too great of loss to run the unit properly. After a temporary reprogramming/reconfiguration, I'm now running it as a single head remote with only one of the 131 footers until we figure out the final solution (and it works fine).
We have searched the XTL series of service manuals and cannot find reference to a maximum total footage for combined control cables for the dual head XTL2500 or the up-to-four head XTL5000. Many of M's tech manuals list the maximum combined length when it is known to be an issue (MC3000 desksets, for example). Does anyone have any factual reference to these numbers for the XTL or a friend at the product group who might be able to shed some light?
One of the runs in the building could easily have been made with a 100' control cable. I plan on switching its 131 footer with a 100 footer, but hold little hope that a 31' reduction on only one cable will gain me the needed signal to fix the problem.
Anyway, thanks for any references you might be able to steer us to on this problem.

- Jeff
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Bill_G
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Re: XTL Multi-head Combined Control Cable Limit?

Post by Bill_G »

XTL's have a 131ft ctrl cable option?
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escomm
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Re: XTL Multi-head Combined Control Cable Limit?

Post by escomm »

Bill_G wrote:XTL's have a 131ft ctrl cable option?
HKN6164A CABLE,REMOTE MOUNT,131 FT
Jim202
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Re: XTL Multi-head Combined Control Cable Limit?

Post by Jim202 »

You have to remember that the remote heads are using a data flow between the radio and the control head. It is using an SB9600 format. This is sort of a cross between an RS232 and RS485 depending on how you look at it.

Being that it is RS232, go do some homework and see how many feet it is rated for.

The next comment I would pass, is did you try the radio and control heads outside of the ceiling runs with the long cables on the bench? If not, then shame on you. But it probably would work with one long cable, not sure about both.

So the next comment is what is different with the long cables on the bench and the long cables in the ceiling. My bet is the dumb installers ran the cables helter skelter with no thought in mind of the power cables in the ceiling and the light fixtures. You need to stay away from them and make sure if you cross any unshielded power cables, do it at a right angle. Never run along side of power cables with your data cables.

Last comment is have you tried the connections with only one long cable connected? You might find that the combined length of both cables being daisy chained is way too long for the data bits to stay in line, not get distorted and have an acceptable level to function.
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Bill_G
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Re: XTL Multi-head Combined Control Cable Limit?

Post by Bill_G »

escomm wrote:
Bill_G wrote:XTL's have a 131ft ctrl cable option?
HKN6164A CABLE,REMOTE MOUNT,131 FT
That will definitely reach the back of your Suburban command vehicle.
Batwings21
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Re: XTL Multi-head Combined Control Cable Limit?

Post by Batwings21 »

Uh, I really don't like the idea of powering the heads from different astron power supplies. I would suggest powering the radio and heads from the same power supply.
Jim202
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Re: XTL Multi-head Combined Control Cable Limit?

Post by Jim202 »

Batwings21 wrote:Uh, I really don't like the idea of powering the heads from different astron power supplies. I would suggest powering the radio and heads from the same power supply.


Using a common power supply is the best way to operate the heads. However, that may not be a good option on this long of a run. Having had to do this a couple of times in the past on older radios, I don't see a major problem. The +12 volts is plus 12 volts no matter how you look at it. It would be a good idea to have the ground of all 3 power supplies tied together, but that may not be possible. So now your only option is to use the AC power system ground wire as a common ground between your supplies. You will just have to live with the ground loops and the issues that may crop up in this case.

Sure there will be those that will jump in here to bring the rains of the sky down on my comments. Bottom line is you do what you need to to make things work. If you think you have a practical solution to this persons problems, by all means jump in with both feet and let us hear what you have to say.

Jim
Batwings21
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Re: XTL Multi-head Combined Control Cable Limit?

Post by Batwings21 »

Well here's more info for you, but probably not what you wanted to here.

First I'm fairly certain the O series heads use sb9600 any more. Doesn't really matter anyways...

Second I agree with Jim202 that you may be able to function with separate supplies, but I would like to see all the grounds tied together with a separate ground wire of decent gauge. (even as a test ran under the ceiling to see if that helps at all.)

And lastly and probably worst is the maximum length for a multiple control head xtl is 131ft. So it just may not work no matter what you do. Here is a cut and paste from the xtl5000 multi-head Ecat page.

8: Remote Mount Cables

***THERE IS NO STANDARD 17' CABLE OFFERED FOR A MULTI CONTROL HEAD CONFIGURATION. YOU MUST ALWAYS ORDER ONE CABLE PER CONTROL HEAD***

***Therefore, if a GA00092 Dual Control radio is desired, then the total Qty of cable options should be double the main line item Qty. Please see "Example Configurations: Dual Control" (top of page) for help***

***Total cable length may not be greater that 131 ft (40 meters)***

Description Nomenclature APC Price
ADD: REMOTE MOUNT CABLE 3 METERS (10 FT) G618 514 $10.00
Corresponding kit: HKN6170
ADD: REMOTE MOUNT CABLE 5 METERS (17 FT) G628 514 $15.00
Corresponding kit: HKN6169
ADD: REMOTE MOUNT CABLE 10 METERS (30 FT) G610 514 $25.00
Corresponding kit: HKN6168
ADD: REMOTE MOUNT CABLE 15 METERS (50 FT) G609 514 $35.00
Corresponding kit: HKN6167
ADD: REMOTE MOUNT CABLE 23 METERS (75 FT) G607 514 $45.00
Corresponding kit: HKN6166A
ADD: REMOTE MOUNT CABLE 35 METERS (115 FT) G879 514 $55.00
Corresponding kit: HKN6165
tvsjr
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Re: XTL Multi-head Combined Control Cable Limit?

Post by tvsjr »

+12 might be +12, but ground is likely not ground (at least, not in any building I've ever seen, and only in some telco/RF sites).

Frankly, what you're trying to do is not what those long cables were made for. Those cables were built for large mobile incident command vehicles. In some instances, you might have one long cable going to a remote head up front (for use while the vehicle is in motion) and a short cable to a head in the rear. But they were never intended to be strung throughout a building.

For a stationary installation, the right answer is an XTL5000 consolette installed in the equipment room (where routing for antenna coax, etc. isn't a challenge), with MC3000 desksets in the facility.
JeffFireRadio
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Re: XTL Multi-head Combined Control Cable Limit?

Post by JeffFireRadio »

Batwings21...thanks, that's exactly what I was looking for. I appreciate you taking your time (and actually answering the question posed). :) Same to Jeff at escomm. Thanks to all who chimed in.

For the record, I inherited this mess after(!) the original installation wouldn't work. I came in to program the radio onto the trunking system and was guilty by association when it wouldn't work after my hitting "write to radio". I was just trying to get these good people an answer and solution, if possible. We have a very competent MSS here and I'm guessing they didn't have this tidbit of information either, or they wouldn't have installed it in this configuration. This was the setup the customer specified and I'm assuming they didn't have the $$$ for an XTL5000 W9 Consolette, a radio modem (junction box), and MC3000s. Again, the good news is that it's working on a single head now at the "important" workstation and that gets their immediate need met.

Happy turkey day to all!

- Jeff
pluto1914
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Re: XTL Multi-head Combined Control Cable Limit?

Post by pluto1914 »

I hope this helps.

I have an XTL5000 with 2 O5 control heads installed as a base station. They are both on 115ft control head cables and both come from the radio itself. The heads are powered by independent power supplies.

Now the catch. This radio was purchased over a year ago and had to go back to Motorola to fix some issue with the longer control heads...

David
JeffFireRadio
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Re: XTL Multi-head Combined Control Cable Limit?

Post by JeffFireRadio »

Ah, the plot thickens. Thanks for the information. I'd love to know what was done (firmware refresh, hardware update, ???) if you have an invoice or service report from when it came back.
Jim202
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Re: XTL Multi-head Combined Control Cable Limit?

Post by Jim202 »

I agree with Pluto, in that he ran both heads with their own cable directly from the radio. There3 are more than one blue connector on the radio itself. In running 2 different cables from the radio, your sort of cheating and probably get away with the long cables that way.

I would have to spend a few looks at the radio service manual to try and figure if each cable connection has it's own driver or if they are common off of a single cable driver.

Jim
com501
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Re: XTL Multi-head Combined Control Cable Limit?

Post by com501 »

There is a physical limit to how far a USB data cable can run. Two 131 foot cables in two different directions does work, but not daisy chained. For all intents and purposes you can consider the data cable from the radio to the control head to be a usb cable with fancy connectors.
JeffFireRadio
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Re: XTL Multi-head Combined Control Cable Limit?

Post by JeffFireRadio »

Thanks for the reply. These are run as two separate cables from the drawer, not daisychained. That was someone else's assumption despite what I conveyed in my original text to the contrary. And, two-131 footers isn't working. But, one of the recent replies gives hope that there may be a solution. More to follow, I'm sure. Thanks again.

- Jeff
com501
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Re: XTL Multi-head Combined Control Cable Limit?

Post by com501 »

What is the firmware version? Can you bump it up to something newer?
JeffFireRadio
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Re: XTL Multi-head Combined Control Cable Limit?

Post by JeffFireRadio »

They were flashed in March of 2010 and I just looked at their firmware version a few days ago. 12.xx.xx. or 14.xx.xx comes to mind, but I'll read one and find out for sure. I haven't looked at the version notes page on here yet to see if that was something addressed in a recent hosp/dsp update. Off to do that now.
Dorf411
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Re: XTL Multi-head Combined Control Cable Limit?

Post by Dorf411 »

A bit of a thread dredge here but, Jeff did you ever resolve this problem? I have a similar install requirement where I would probably need 131ft on one control head and another head with 10ft. Will I be safe with this install or do I need to go with 115ft and 10ft? Both control heads would go back to the drawer unit instead of being cascaded. Anyone?

Thanks,
JeffFireRadio
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Re: XTL Multi-head Combined Control Cable Limit?

Post by JeffFireRadio »

I haven't been back to that project yet. We're living on one head at a time for now. Our long cable (131') was run by installers and actually could have used the next shorter one (100', if memory serves me), as there is about 30' coiled up as extra. So, I plan to re-pull a 100-footer and hopefully rectify my loss problem. I will post an outcome once I get back to it. Sorry, no fix to report just yet. Good luck.
CTAMontrose
was grem467
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Re: XTL Multi-head Combined Control Cable Limit?

Post by CTAMontrose »

Something is sticking in my head that there was a firmware update to the XTLs about the same time the 131' cables came out that addressed this. Could be wrong, but I could swear it was in the release notes.
resqguy911
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Re: XTL Multi-head Combined Control Cable Limit?

Post by resqguy911 »

CTAMontrose wrote:Something is sticking in my head that there was a firmware update to the XTLs about the same time the 131' cables came out that addressed this. Could be wrong, but I could swear it was in the release notes.
Subscriber 6.14 (SR7.8.5)– Mar 2010
Abstract: XTL O5 Control Head Interconnect cable length extension
System Platforms Affected: Any
Special Configurations: Control Head to Transceiver required cable lengths greater
than 130 ft.
Description: The interconnect cable length for the O5 control head was increased
from a maximum of 260 feet combined for 2 control heads to a maximum combined
length of 325 feet. A maximum of 2 control heads are supported in this extended
configuration. The maximum cable length for a single control head is extended to
175 feet.
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