Apologies and another question

[mikefamig]

Are you properly terminating that end of the databus?
 
As you move the various equipment around, you'd also need to consider where the terminating resistor is....

Yes the terminating plug is always in the next available dbh outlet when the DBH is connected. Read my earlier posts and you will see the different configurations that I have tested and all failed. I am down to just the cat5 connected from the control to the p212s and nothing else on that second data bus. No DBH, no zones no nothing but a power supply an the elk is chiming violated zones randomly. When I disconnect he second data bus it returns to normal.
 
See post #38
 
Mike.

 

[mikefamig]

The wiring describe below doesn’t make any sense. The keypad and P212 (located in garage) need their own cat5 home run wiring. If you have M1XIN then a third cat5 is required. I would just wire the keypad by itself and use one area. If this works, then you can change the definition for second keypad to a different area (common practice with garage). I understand you could probably daisy chain all the garage devices on one cable, but you are really asking for trouble trying to accurate figure out which device terminates the bus.
 
>At the control the cat5 has the two green data wires connected to A and B data and the two brown
>wires twisted together and connected to common or 12v-. At the garage the same cat5 has the two
>green A and B data wires connected to the A and B data on the supervised p212s power supply and the
>brown pair connected to the common on the p212s power supply(no termination).  The data bus then
>leaves there and goes to the dbh which in turn connects a keypad, a xin and an ovr and terminates with
>the dbh terminator plug.
 
From the thread’s description, it sounds like you have a wire crimping or zone termination issue. I have experienced the similar random bus bad behavior caused by a poorly built RJ-45 DBH connection.

I disagree with your wiring plan to use a cat5 for each device. The cable run from the control to the second building is 250' long and the DBH in the second building allows me to run just one cable from the control to it and then it attaches all of the devices in the second building.
 
When the elk has two home run data buses the buses are connected to the control in parallel. There is no port A or port B. The two cat wires connect to the same terminals on the control. Each of these two cables goes to a DBH. Each DBH supplies a loop in each of the two buildings.
 
I like your idea of checking the connectors but I have stripped the system down to just the car5 and the p212s and have the same problem. There are no connectors involved.
 
Mike.
 
 

 

[mikefamig]

d.dennerline
 
Thank you for reminding me to check the termination. I try to be very careful but it can get away from me at times. It just occured to me that when I removed the dbh and tested the p212s alone I did not put the terminating jumper on the p212s so that invalidates that test. On all other tests the dbh provided proper termination.
 
Also, when you run two rs-485 cables from the control you have to remove the terminating jumper from the control and put one on the end of each data bus. (page 7 installation manual)
 
Mike.

 

[mikefamig]

I'm grasping at straw now.
 
It just occurred to me and it's a long shot but I am going to test the DBH terminating plug today and make sure that it is 120 ohms across data a and data b as described in the manual.
 
I will also retest the p212s with the terminating jumper installed.
 
If that fails I will try connecting just the dbh powered by the control omitting the p212s.
 
If that fails I will test just the keypad omitting the p212s and the dbh
 
If that fails then I think that I have a bad cat5 cable or a bad control.
 
Mike.

 

[mikefamig]

One DBH has a quite a bit of expandability, so most people don’t use the second RS-485 Port B. Since the onboard jumper JP21 has to be on when DBH is connected to Port A, I think termination methodology changes.  I don’t have manual in front of me.
 
Is my understanding of wiring correct, you only have one cat5 going to the garage. You are trying to daisy chain multiple devices on garage loop and use Port B. You then have a Port A using DBH.

I do not know what you mean by port a and port b. Can you explain? I don't know of any jp21 either.
 
Mike.

 

[drvnbysound]

Yes the terminating plug is always in the next available dbh outlet when the DBH is connected. Read my earlier posts and you will see the different configurations that I have tested and all failed. I am down to just the cat5 connected from the control to the p212s and nothing else on that second data bus. No DBH, no zones no nothing but a power supply an the elk is chiming violated zones randomly. When I disconnect he second data bus it returns to normal.
 
See post #38
 
Mike.

 
This was exactly my point...
 

d.dennerline
 
Thank you for reminding me to check the termination. I try to be very careful but it can get away from me at times. It just occured to me that when I removed the dbh and tested the p212s alone I did not put the terminating jumper on the p212s so that invalidates that test. On all other tests the dbh provided proper termination.
 
Also, when you run two rs-485 cables from the control you have to remove the terminating jumper from the control and put one on the end of each data bus. (page 7 installation manual)
 
Mike.

 

[drvnbysound]

I do not know what you mean by port a and port b. Can you explain? I don't know of any jp21 either.
 
Mike.

 
Look just below the port you are using now. There are two male connectors. 
 
I don't use these, but use the standard terminations for pulled wire as well.
 
EDIT: Here's a picture from the manual:

 

[mikefamig]

One DBH has a quite a bit of expandability, so most people don’t use the second RS-485 Port B. Since the onboard jumper JP21 has to be on when DBH is connected to Port A, I think termination methodology changes.  I don’t have manual in front of me.
 
Is my understanding of wiring correct, you only have one cat5 going to the garage. You are trying to daisy chain multiple devices on garage loop and use Port B. You then have a Port A using DBH.

Each data bus uses cat5 wired to the control. One goes directly to a dbh that services the house wireless and keypad. The other goes to a p212s and then to a dbh that services the garage keypad, zones and outputs. 
 
Mike.

 

[mikefamig]

Look just below the port you are using now. There are two male connectors. 
 
I don't use these, but use the standard terminations for pulled wire as well.
 
EDIT: Here's a picture from the manual:

Thanks I get it now.

 

[Del91574]

Without getting into a pissing match, but from doing a TON of 485 wiring on various access control panels that are far more complex than an M1, with far more data being transmitted, a terminating resistor is not completely necessary on the bus. It is, however, recommended to be installed to help minimize data bus reflections, which causes small data errors or issues over time.
 
In the OP's case, he has 2 branches, so there should be NO termination on the M1 board, and in the case of a DBH, no field terminations would need to be enabled on any device with the exception of the RJ45 being plugged into the next available port on the DBH
 
I find it amusing however, that Elk contradicts themselves....J1 and J2 on the board were specifically stated to be used for a temporary testing connection ONLY, but in the case of the DBH they state that you can connnect the hub to either J1 or J2 using the accessory cable (read the FPN on the bottom of pg 7 of the installation manual).

I would be curious, however, as to what area the 212's are attached to, as they are viewed by the system as a keypad, which might be part of the issue.

 

[ddennerline]

The M1DBH documentation does describe how two DBHs can be connected together using a cross-over cable. You would use the garage RJ-45 for cross-over cable. At the same time, the M1DBHR (different product) seems to indicate that you cannot remote a second DBHR. I don't know if M1DB has same limitation.
 
Without M1DBH, ElkM1 provides two seperate loops via data A and B. I wonder how the M1DBH patches both the A and B data buses together.
 
I think you might want to obtain support from Elk (through your dealer) and draw out your network picture.  There are so many variables involved.I could not find a application note how to hook up a secondary building using two DBHs. There is a limit on the length of RS-485 bus.
 
Maybe it might be better to use *one* M1DBHR for entire system instead of two M1DBH as the DBHR seems to do a better job at handling separate isolated branches with multiple devices on each branch.

 

[mikefamig]

I would be curious, however, as to what area the 212's are attached to, as they are viewed by the system as a keypad, which might be part of the issue.

DEL
 
There are no longer multiple areas in my system -I rebuilt the account with just one area. When I attach and enroll the second branch of the rs-485 is when I have trouble. The system has been just chiming violated zones for no known reason.
 
See post #38 but I have to make a correction to what I said in that post. When I had only the p212s attached to the rx-485 I forgot to put the terminating jumper on the board. Yesterday I attached the p212s with the proper termination and the sy=stem has been behaving normally so far. Today I will add the dbh and if the problem returns then I may try connecting a keypad without the dbh and see what happens. I'm beginning to suspect that I have a hardware failure or maybe a bad wiring connection in on of the rj45.
 
Mike.

 

[Del91574]

The M1DBH documentation does describe how two DBHs can be connected together using a cross-over cable. You would use the garage RJ-45 for cross-over cable. At the same time, the M1DBHR (different product) seems to indicate that you cannot remote a second DBHR. I don't know if M1DB has same limitation.
 
Without M1DBH, ElkM1 provides two seperate loops via data A and B. I wonder how the M1DBH patches both the A and B data buses together.
 
I think you might want to obtain support from Elk (through your dealer) and draw out your network picture.  There are so many variables involved.I could not find a application note how to hook up a secondary building using two DBHs. There is a limit on the length of RS-485 bus.
 
Maybe it might be better to use *one* M1DBHR for entire system instead of two M1DBH as the DBHR seems to do a better job at handling separate isolated branches with multiple devices on each branch.

The OP does not need any special cabling or considerations if 2 DBH's are connected and wired in parallel at the control. The only item that requires consideration is the removal of the termination jumper at the panel (JP3). There is no need or requirement to negate a second DBH or require one for this installation. The only reason why one would be negated or installed would be to facilitate easier field connections for bus devices and in technicality, he could have 8 or 10 hubs installed with no ill consequences. Without getting into specifics DBHR's are a different animal, but you can also have much more than a single one installed as long as the terminating jumpers are paid attention to. There's reasons why they state to NOT install them in the field, but that is a different discussion altogether.
 
The DBH does not provide any special connections or feed throughs when cascading from another DBH...all you are doing by connecting a crossover cable is taking the cables that would be "out" on the RJ45 and moving them to an "in" position on the secondary DBH.
 
At this point, based on the issues described, I'd start investigating the cable that connects the garage branch and pinouts as appropriate. Possibly take the direct burial, restrip and reterminate, then run that bus, terminated in the field, with no devices and then move a single device at a time to see when the errors start to occur.
 
As an aside, what is the total overall run of all attached devices? Remember, the M1 can only handle 4K total length, and by using a Cat X cable, that length is halved.
 
Wiring multiple busses and devices on an M1 isn't rocket science, there's really only 2 ways to do it and no real network topology or variables. You either bring 2 data wires to the device and feed the next device downstream or you don't (and terminate the bus at that device). The DBH just forces your hand to feed/return the data bus and install the 120 ohm resistor in that little RJ at the hub. No different than if you ran enough conductors, tied through, and installed your own 120 ohm resistor at the last data pair.

 

[mikefamig]

At this point, based on the issues described, I'd start investigating the cable that connects the garage branch and pinouts as appropriate. Possibly take the direct burial, restrip and reterminate, then run that bus, terminated in the field, with no devices and then move a single device at a time to see when the errors start to occur.

 
As an aside, what is the total overall run of all attached devices? Remember, the M1 can only handle 4K total length, and by using a Cat X cable, that length is halved.

 
 The direct bury is about 250' long and my total system does not come anywhere near 4000'. I'm sure that it is less than 1000'.
 
The 250' direct bury is wired directly to the terminals on the control on one end and wired directly to the terminals on the p212s at the garage. There are no rj-45's or other termination to be concerned with. There is a jumper on the p212s to terminate the data bus. Nothing else is connected on this leg, only the p212s.
 
The second branch of the data bus is also wired directly to the terminals on the control on one end and directly wired to the terminals on a dbh in the house.The dbh has 1 wireless tx and one keypad attached to it using rj-45's and this leg of the data bus is terminated with a dbh terminating rj-45.
 
I have been focusing my attention in the garage because the problem goes away when I disconnect the garage but it may be possible that I have a bad connection in the house and that by adding the garage branch and lengthening the data bus I am just worsening the existing problem in the house and symptoms show up in the way of errant chimes.

 

[Del91574]

Using Cat X cable brings the M1's total bus length down to 2K OAL. To start eliminating components, you can always move them to the panel and connect everything there. No issues means the problem is the media and not firmware/programming.
 
I would start by disconnecting the buried cable and then restrip and, assuming it's flooded cable, remove the grease and meter everything to ground. I don't know of the cable construction, but usually it's a poly outer, then a foil/flooded and then the inner conductors laid within the gel. Very easy to nick and cause a bridge to ground, especially with burial.
 
Let's get back to basics....what is connected to the bus and where (I'm being a little lazy and don't want to go re-read and wade through posts) You state the bus goes from the house to the garage and only to a 212, nothing else? Jumper removed at the panel?

I doubt the bus within the house is the issue, but redoing connections is usually an easy and logical step.