MCP Changes in time offset when using Averaging
Status: Open - will be fixed in windPRO 3.2 Service Pack 1
Fixed in build: 670
Two calculation is made in MCP2005 and MCP, will provide different results if Averaging is enabled.
The reason is that if e.g. the reference data is 10 minute data, and the reference data is 1 hour data, then the time interval for averaging is different in the two MCP modules. For e.g. time 05:00 reference time, the MCP2005 will average the time interval 04:05->05:05, whereas the new MCP module will match 04:55->05:55. To counter for that, the user could set the time offset to -50 in the new MCP module to get the same results as in MCP2005.
In this service pack, the matched time interval will be set to: 04:35->05:35, for measured data where the entry represent the preceeing 10 minutes, and reference data represent the exact time (as is the case for meso scale data), this should give the best results. To get the same results in MCP2005 and the new MCP module, the time offset in the new MCP module should be set to -30.
To counter for this, and ensure that results from existing MCP calculations gives the same result. MCP calculations made before this service pack, will have the Time offset automatically changed for MCP Sessions which use averaging.
EMD suggests to always use the "Auto" button on the Filter page to find the offset which gives the best coorelation between measured and reference.