problems linking pm876 smyphony to project
we are trying to embed redundant pm876 symphony controllers to a meldoy composer project. the two main problems are:
(1) when trying to link the device (cubical layout) it fails saying "the pm876 at epc017c09 cannot be linked to ab0". same for redundant controller. though there seems to be no possiblity to modify ab0 net. how to interprete this error? melody analyzer by the way can connect to both redundant controllers without problems, indicating them as passive. another redundant controller pairn was succesfully embedded already without having this error.
(2) one redundant controller pair has to be installed in a pm895 19" rack. unfortunatelly i cannot find any docu for it. i miss the code switches s2 and s3 in order to set the cabinet number. there is just s1 to set the tier identifier a,c,e,g. the controller pair is declared as epc016a09/11. after having set s1 to "a" and running epi, the controllers unfortunatelly cannot be connected to from meldoy analyzer. is it supposed to work like this or how the cabinet number can be set?
thanks for any hints. please ask for details you might need
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(1) It is difficult to find a problem without detailed info. I expect that happens when you try to link or reload PM876 to the existing Melody project. Probably previous controller had already connected some c-net subscripters and you are not allowed to link or reload another one to the same position when previously connected c-net subscripters are not available.
(2) You probably mean PH895 standard rack (not 19"). This rack doesn't have switches for cabinet number setting. PH895 is designed to be together with Melody power supply unit which includes Fuse module CS435-P. And cabinet number is set on CS435-P which provides EPC number for 1-4 pieces of PH895 in cabinet.
thanks for your reply,
well c-net participant numbers and addresses don not collide. if that's what you mean.
i connected first and second controller via coax cable on AB0 (do not have hardware yet to connect redundant net AB1 though) .. and voila the error disappeared. even the yellow frame in the cubical layout dissapears. unfortunately it stays another error "global configuration data cannot be loaded". Analyzer tells that both redundant controllers are passiv and have an undefined status.
The main challenge for linking controllers in melody is to have the linking state of the project and the reality in sync.
For example, you cannot take a backup of a running project, take a controller and try to make it running as a 'simulation' of one in the project by giving it the same EPC.
But if you have planned the controllers (the only controllers?) in a project, they are wired correctly and (if other controllers exists) the link status of other controllers in project are in sync with the real controllers (none is removed), it should work fine.
There is one exception - if you try to link the first controller pair, you should disable the redundant one in reality(the real hardware) and perform the linking in Composer twice. After the second try the main controller should be linked successful (yellow frame must be removed). Now enable the redundant controller in reality and make another try. Now both controllers should be marked as linked. This special treatment is only required for the first pair of controllers.
Linking the controllers with Melody Analyzer is NOT a good proposal in general, because the project and real controller link status will be out of sync typically. And so you will get in trouble with the next linking actions. There are some rare special situations where it makes sense, but ....