Liebert DS Modbus Comms

[nthwing]

Anyone have any experience integrating to Liebert's DS CRAC's with modbus? I'm working on a job with 12 new CRAC's and I'm running into an issue with points going to null (specifically all the numeric points) and binary points changing state without any change on the CRAC itself. I noticed this problem when we started getting compressor #2 high pressure alarms from one of the units. When the unit was checked the compressor was not tripped, and there was history of an alarm in the CRAC's memory. The problem seems intermittant and is only solved temporarily by pulling the comms card on the CRAC and plugging it back it in. I've called their monitoring tech support and they reccoemended that I call the mechanical tech support because it may be an issue of communications between the card and the CRAC's main board. The comms cards are at the latest revision level, and the main boards are not as I understand it. When I talked to the mechanical guys at Leibert they said they've never heard of the issue, and assured me that the revision level on the board is fully compatible with the revision of the comms card.

Any ideas?

[MaxBurn]

I know they are in the process of rolling out new firmware for the DS iCOM controllers somewhat recently. The firmware on the IS485-LBDS interface card can be checked with hyperterminal and the firmware is a download from www.liebert.com, right near where the modbus point lists are for that option card. The firmware for the unit is under tighter wraps and only released to certified trained people though. I want to say that firmware in the iCOM is like 1.04.xxxx now but I could have that wrong.

By the way the *-LBDS cards are the specific ones for the DS iCOM units, the others will not work in them but I guess you have the right ones as you have some functionality.

Next time when one disconnects connect hyperterminal to the service port on the card and I believe somewhere in there it will say whether or not it has comms to the unit, that's something you can screen-cap or log to file to prove you have a problem to support in the unit and not something wrong with the modbus link.

I can tell you it hasn't been all rosey for this unit but most of the comm problems we have had were either in the controlling of setpoints or that and a mixture of understanding what is needed to turn off the built in teamwork modes where they can talk amongst themselves to determine failover and not fight with one humidifying and the other dehumidifying in the same room.

[crab master]

Any more update to this? I have a single DS i-Com unit that is randomly tripping on the same exact alarm. I've checked the registers and the register is correct for Comp 2 High Pressure 10041. It trips for like a minute and then clears on its own.

This unit was installed brand new in June 2010 so I don't know what firmware it is yet and we've got 5 more units that will be installed by next month, so I need to get this resolved.

We have link 45 other Lieberts, a few System 3's and most the model before the DS-icom, but I am not getting this random alarm on any of those models.

[MaxBurn]

The firmware for the intellislot card is posted on the public website but only the trained techs can access the firmware for the unit itself. The absolute newest ones are using a different intellislot card now too. Should get the techs out there to do under warranty imo.

[crab master]

Thanks, I have an email into the equipment provider. So the firmware upgrade should do it or do you recommend we push for the newer card?

[hotrod53]

These alarm points can trip intermittant alarms if the alarm buffers are not set correctly. Just because they are set to auto configure doesn't mean that the alarm buffer data comes in right, you have to touch it up. I had this problem as recently as this week and many times in the past.

In my case I am using a Sitelink-12, under protocals there is a parameter section where you configure the alarm buffers. I had this issue this week with the I-com 2mb program tripping a general alarm intermittantly.

The Techs have a cheat sheet that tells them what the buffers should be set for based on what program you are using. If you have other like units already working, compare their alarm buffer settings and make the new one match. Once set correctly, the issue will reolve.

[crab master]

Not sure I am following you on this. This is definitely a longer 'blip' as I have a 30 second delay in the monitoring controller before it will send out the alarm. It a TAC programmable gateway, so I added a 30 second delay on the monitored register point. Oh and the alarm log in the unit does not show such an alarm event happening.

[MaxBurn]

He is referring to a sitelink and I think you were referring to an option card speaking modbus right?

[crab master]

Correct

[hotrod53]

Oh, I missed that. Yes, I integrate thru a Sitelink which sounds different than what you are using.

[NathanVanKCMO]

Sorry to hijack this thread but we just changed out 5 liebert and datac units. Unhooked the 77 78 data wires and hooked up to the new Liebert DS with icom. Swapped the IGM cable in and reset the crac. No com
With site link. Help! Please? Do we need to hook up a computer to the site link?

Thanks?

[hotrod53]

So it sounds like you disconnected the plug on the circuit board marked IGM and plugged in the plug marked Intellislot. Did you plug into the Intellislot using the supplied blue cable and set up the protocol using hyperterminal? You need to set that for IGM and do a save and restart. Is your protocol on the unit's network page set for Velocity and did you do a save and restart after changing that? Once that is all done, be sure that you have the correct I-comm 2mb program in there, your auto configure on YES, and cycle power on the Sitelink.

Be advised, we recently ran into an issue where the intellislot and IGM cables were labeled backwards.

[MaxBurn]

Right now there are three different ways and two different option cards to connect a DS unit to a sitelink. Sort of in a transitional period at the moment.

If the old units were AM (LAM) style and you want to avoid a site visit for the sitelink programming then you can land comm wires to 77/78, plug in that pigtail RJ11 into the logic board, and set the communication options to IGM in the unit. Save and reboot. Then the unit will emulate the previous AM unit minus some things like run hours.

The other two options require some sort of option card, if you have one.

[NathanVanKCMO]

Right now there are three different ways and two different option cards to connect a DS unit to a sitelink. Sort of in a transitional period at the moment.

If the old units were AM (LAM) style and you want to avoid a site visit for the sitelink programming then you can land comm wires to 77/78, plug in that pigtail RJ11 into the logic board, and set the communication options to IGM in the unit. Save and reboot. Then the unit will emulate the previous AM unit minus some things like run hours.

The other two options require some sort of option card, if you have one.

Wow. Sending messages on my iPhone makes me look like a hack. Ok, so let's try this from a real PC :)

Thanks for the reply. We did manage to get the the wires landed and the pigtail in place and even find the place to change the IGM but the CRAC wanted to revert to Velocity on restart. So we must not be saving correctly. Any tips on that?

Rebooting the sitelink is just power off and then back on?

Thanks for the help. I'm looking forward to becoming more adept at these controls. Go Liebert, death to DataAir :)

[MaxBurn]

Same screen you change to igm on has a save and reboot option at the bottom.

Sitelink needs to be programmed to lam for this to work, what was the logic level of the ac that was removed?

[NathanVanKCMO]

Same screen you change to igm on has a save and reboot option at the bottom.

Sitelink needs to be programmed to lam for this to work, what was the logic level of the ac that was removed?

I'm still trying to figure out the logic level. After successfully changing the new cracs to IGM and doing a save reboot I notice that the site link 12 module
Does not indicate any activity on the 2 unit ports for the cracs I just modified. Is there still hope? :)

[MaxBurn]

On the old unit there is a wiring diagram, usually the logic level is listed on the bottom like L00, L03, L10, AM, AG etc. I could probably decode the part number too.

Reset the SiteLink and let it reset the buffer sizes and see if it starts working. I don't suppose there is any record or paperwork in the sitelink can about how it was setup?

[NathanVanKCMO]

The model number is FH199AUA00
Serial number is not so obvious. Maybe the P19707 on a glossy sticker below the wiring diagram.

Is resetting the sitelink cycling the power switch on it. I'm a bit gun shy being new to these.

Thanks again for your help.

[NathanVanKCMO]

Btw there is also a sitegate-e and a siteI/O

As far as info on how it was setup I have a tag and a site number on the panels

[MaxBurn]

Darn, do you have a year on it? Before or after 1999? That part number decodes two different ways depending on the year.

Before 1999 level 00 logic level, meaning programming change now required in the sitelink. These usually have lamps on the front for different alarms, likely no digital diaplay on front.

If post 1999 and the old unit had a 4 row LDC display sounds like you are in luck, that should have been using the LAM program via 77/78 to the sitelink. That new icom unit when set to igm should emulate the communication of that older unit.

Cycling the power on the sitelink wont hurt anything, assuming the battery is ok. With those other modules there it sounds like there is a sitescan front end on site?

[NathanVanKCMO]

Yep, it's way before 1999. Probably more like 1989, or older.

Ok, well we'll call out the local Liebert guys. Thanks for your help.

Nathan

[MaxBurn]

Do you have one of the 485 intellislot option cards for the unit? Thats the best way to get info out of them, more info available.

[NathanVanKCMO]

I don't, maybe back at our hq in another city. Alas I am at the end of my resources :(

Thanks again though.

Nathan

[OldLGSTech]

The model number is FH199AUA00
Serial number is not so obvious. Maybe the P19707 on a glossy sticker below the wiring diagram.

Is resetting the sitelink cycling the power switch on it. I'm a bit gun shy being new to these.

Thanks again for your help.

You have a level 00 AC unit. The model number should have a dash in it e.g.
FH199AU-A00. The numbers or letters after the dash tell us what IGM you have.

[crab master]

Bump - I am still having this happen. Interesting part is we did the firmware upgrade awhile back on 2 units one right after the other. Got the same High Head Press Cir. 2 alarm even after the upgrade so I extended the time delay on the alarm point out to 75 seconds, but that isn't enough. Oh to add to it the first unit tripped and then 16 minutes later the 2nd unit tripped. Coincidence the time is such that it was likely the time it took to upgrade the firmware from one unit to the second unit?

By the time frame on the alarm delay on and then the alarm clearing I may have to take this out to a 175 second delay...

Anyone heard anything or any other update? TIA

[MaxBurn]

Bump - I am still having this happen. Interesting part is we did the firmware upgrade awhile back on 2 units one right after the other. Got the same High Head Press Cir. 2 alarm even after the upgrade so I extended the time delay on the alarm point out to 75 seconds, but that isn't enough. Oh to add to it the first unit tripped and then 16 minutes later the 2nd unit tripped. Coincidence the time is such that it was likely the time it took to upgrade the firmware from one unit to the second unit?
~

You had iCOM DS units with 485 cards speaking modbus right?

Was "a while back" around 28 days from when you did the update to when you got the alarm?

The good news is they are still working on it and may have found the smoking gun for this whole problem. I'm not really privy to the details.


Meanwhile we have a similar problem with the units talking IGM out of a 485 card but instead of that alarm we get loss of communications. We have a counter we watch and when that number goes away or gets reset we know that the unit lost comms between the iCOM controller and the 485 card. That situation triggers an extra 330 seconds delay for a loss of communication, only when that counter is in that state.

You could do something similar. Do you have temperature trending on a cov? Do you look at the history and see that it goes to zero during these events? I think it should because the unit isn't senting values to the 485 card and if that card is responding to modbus it should be saying zero. If you are able to see that then you could use some logic to trigger a special higher delay time for that one trouble alarm. Or disable it when temp = 0. Or if your units didn't have a compressor you can turn it off.

[crab master]

You had iCOM DS units with 485 cards speaking modbus right?
Yes


The good news is they are still working on it and may have found the smoking gun for this whole problem. I'm not really privy to the details.
I hope so cause I am tired of complaining about this and the local dealer and vendor are both saying I am the only one....It's nice to have this forum though, cause I hate it when they say such acting like it is a problem with our BMS and not theirs...

On the other items I will have to log in and look.

[krac]

Looking to start/stop some new Liebert DS units with factory installed Modbus rs-485 intellislot cards from a Jace and little confused how to mapp the registers that only have a coil number.
From the docs
Data Point Status Coil Bits
VSD Fan speed 10022 22 1
Unit Control - 25 1
Reset Alarm - 26 1
Acknowledge Alarm - 27 1

Coming up blank on adding coil only points to a Jace Modbus network.

[MaxBurn]

http://www.emersonnetworkpower.com/en-US/Products/Monitoring/Documents/SL-28170.pdf

That should be the points list. I don't see those on a DS.

[krac]

Page 12 has the unit control point listed, but no status register just a coil number.

[MaxBurn]

If I am not mistaken function code 5 is force single coil, use that for those points 25-37. For the status on those they are elsewhere in the points list where they can send a large number or where more appropriate for alarms etc.

[krac]

Looks like it maps to a normal Boolean Writable. The unit I was testing had been stopped locally so the remote start doesn't work which is consistent with the older System 3 control. For some reason the Local Off point (Reg 30100) is not changing state but I can deal with that later.

Thanks for the help Scott.

[krac]

Having another issue with finding the Modbus register for the chilled water valve position. The documentation only shows Compressor Utilization (30104) but that point faults when mapped into AX.
Every other point seems to behave as expected.

[MaxBurn]

I think you are looking for something like percent cooling and possibly stages? Pretty sure one of those reflects valve percent on CW units.

[krac]

Liebert Tech support confirmed that I should use register 30104 which is listed as Compressor Utilization, however that point faults when I map it into the Jace. When it didn't work I mapped in a bunch of the registers from 30102 up to 30114 just to see I could find it.