Parker 890 drive HOT fault.

Hello electrical@nuhasoman.com.  

I will need to check with one of the design engineers regarding the board numbers you reference.  In general, if the "Incompatible STO Test Record" alarm occurs the drive needs to come on an RMA for repair/correction.  However, I can also check with design on that.  Are you using the STO inputs/features or simply jumpering them defeated?

I will run the questions on the repair parts and STO alarm by a design engineer in the morning and post a follow up.

In terms of the HOT alarm, your description implies a hard circuit failure or something damaged in teh assembly, leading the fault circuit to mis-read the heat sink temperature, thus no matter how long you let it sit (typically 30-45 minutes is plenty of time for a unit to cool back down to ambient all things considered) it shows that HOT fault immediately and seems to mis-read the temperature.  

1.  Are the drives installed in an enclosure?

2.  Is the enclosure ventilated?

3.  Where are you located?

Hello electricalRavi Prabhat

No, the STO fault cannot be cleared in the field.  The unit would need to come in on an RMA set up through a local Parker store or distributor.  I truly do not know how that might be in Oman as that isn't a region we would sell/service directly.  There will be Parker locations there that can assist you in that.

Regarding the HOT fault, only other question is whether these previous failures were always on a particular 'axis' amongst the three, even if multiple drives have failed over time, where they always installed in the same physical location? 

We are assuming the temperature in that enclosure is always well regulated but in theory there could be times when the air conditioning has failed or is simply not adequate to keep the internal enclosure ambient temperatures within the product operation specs.  Measuring the internal enclosure temperature during normal operating conditions on a hot day would be a good thing to verify.  Won't tell you if the AC has failed at times but at least we know that normally it is within spec, instead of just assuming so because it has an AC system.

Your description also implies you have down repairs in the past.  That is a little confusing as these repair boards are not items we sell directly.  Where/how have you been sourcing the replacement boards?  

Finally, if you have been tearing down the drives to replace boards and any of the internal thermal bonds between the bridge and the heatsink was broken, there is very good likelihood that this bond isn't to factory spec unless the repair technician added thermal compound when it was being rebuilt.  This could results in the IGBT device running much hotter than it should as it can't dissipate its heat energy into the heatsink as efficiently as it should, regardless of the ambient temp.  That could lead to short term HOT faults and then eventually a hard failure (in theory).  

Hello electricalRavi Prabhat

No, the STO fault cannot be cleared in the field.  The unit would need to come in on an RMA set up through a local Parker store or distributor.  I truly do not know how that might be in Oman as that isn't a region we would sell/service directly.  There will be Parker locations there that can assist you in that.

Regarding the HOT fault, only other question is whether these previous failures were always on a particular 'axis' amongst the three, even if multiple drives have failed over time, where they always installed in the same physical location? 

We are assuming the temperature in that enclosure is always well regulated but in theory there could be times when the air conditioning has failed or is simply not adequate to keep the internal enclosure ambient temperatures within the product operation specs.  Measuring the internal enclosure temperature during normal operating conditions on a hot day would be a good thing to verify.  Won't tell you if the AC has failed at times but at least we know that normally it is within spec, instead of just assuming so because it has an AC system.

Your description also implies you have down repairs in the past.  That is a little confusing as these repair boards are not items we sell directly.  Where/how have you been sourcing the replacement boards?  

Finally, if you have been tearing down the drives to replace boards and any of the internal thermal bonds between the bridge and the heatsink was broken, there is very good likelihood that this bond isn't to factory spec unless the repair technician added thermal compound when it was being rebuilt.  This could results in the IGBT device running much hotter than it should as it can't dissipate its heat energy into the heatsink as efficiently as it should, regardless of the ambient temp.  That could lead to short term HOT faults and then eventually a hard failure (in theory).  

https://drive.google.com/file/d/1__YmSkFR19iFJZX45ihXp1wQnpCfL3lu/view?usp=sharing