Hello, I have some basic questions to ask about Profibus.
Tt will be a little long to explain all, but I prefer giving all details to help people understand my problem with the context.
I don't know Profibus very well but today I went to a factory because their automation specialist is on holiday. The reason given was: the CPU S7-400 lost its program by battery default and they needed someone to upload it....
However, when I looked it, the S7-412 had a flash memory card inserted (eventhough it still has a battery?), so I doubted it could have lost its program. I tried to connect with my pc in every possible way but I couldn't. The four first LEDs were full RED (INTF, EXTF, BUS1F, BUS2F), the MPI port (BUS1F) too so impossible to connect. I concluded it was damaged, opened it and confirmed it.
They also had a 24V power supply which was exposed to water and was flashing immediately when powered. It wasn't the dedicated power supply of the CPU, but a sitop powersupply used to supply the I/O and decentralized periphery.
Now here come the problem. The SITOP power supply was replaced by some 24V PS they had in stock. I changed the CPU with another one they had, slightly different. A CPU 412-2 too, but with another reference, and a firmware 5.3 instead of a firmware 3.
When I transfer the HW, it understands that it's not the exact same version, but accept it anyway, and the CPU turn into RUN mode.
However, the profibus is in default. And here is something that surprised me a lot:
Eventough on their Profibus network they have one cable from the cpu profibus connector going to a serial of Siemens and the other going to a first IM151, then a second IM151 and then a HMI, in their hardware configuration, they only have one IM151 (the second one in the topology) and nothing else on the profibus network.
It surprised me because I always thought all slaves must be configured in the master project. But here, no. How is that possible? They told me this program works and always worked witht hat configuration.
The IM151's have the top two led flashing red in the same time for some seconds, then the second one flashing red alone, and then the double flashing cycle begins again.
One other thing, they repaced the first IM151 this month(with added I/O) and told me they just unplugged Profibus connectors then plugged it exactly how it was when they installed the new IM151)
I am in the process of checking the quality of the connections in the profibus connectors, but what others things should I look after?
The HW configuration thing puzzles me. Could the SITOP damage the IM151s? The leds of most the I/O of IM151's are green.
Tt will be a little long to explain all, but I prefer giving all details to help people understand my problem with the context.
I don't know Profibus very well but today I went to a factory because their automation specialist is on holiday. The reason given was: the CPU S7-400 lost its program by battery default and they needed someone to upload it....
However, when I looked it, the S7-412 had a flash memory card inserted (eventhough it still has a battery?), so I doubted it could have lost its program. I tried to connect with my pc in every possible way but I couldn't. The four first LEDs were full RED (INTF, EXTF, BUS1F, BUS2F), the MPI port (BUS1F) too so impossible to connect. I concluded it was damaged, opened it and confirmed it.
They also had a 24V power supply which was exposed to water and was flashing immediately when powered. It wasn't the dedicated power supply of the CPU, but a sitop powersupply used to supply the I/O and decentralized periphery.
Now here come the problem. The SITOP power supply was replaced by some 24V PS they had in stock. I changed the CPU with another one they had, slightly different. A CPU 412-2 too, but with another reference, and a firmware 5.3 instead of a firmware 3.
When I transfer the HW, it understands that it's not the exact same version, but accept it anyway, and the CPU turn into RUN mode.
However, the profibus is in default. And here is something that surprised me a lot:
Eventough on their Profibus network they have one cable from the cpu profibus connector going to a serial of Siemens and the other going to a first IM151, then a second IM151 and then a HMI, in their hardware configuration, they only have one IM151 (the second one in the topology) and nothing else on the profibus network.
It surprised me because I always thought all slaves must be configured in the master project. But here, no. How is that possible? They told me this program works and always worked witht hat configuration.
The IM151's have the top two led flashing red in the same time for some seconds, then the second one flashing red alone, and then the double flashing cycle begins again.
One other thing, they repaced the first IM151 this month(with added I/O) and told me they just unplugged Profibus connectors then plugged it exactly how it was when they installed the new IM151)
I am in the process of checking the quality of the connections in the profibus connectors, but what others things should I look after?
The HW configuration thing puzzles me. Could the SITOP damage the IM151s? The leds of most the I/O of IM151's are green.
