shifted column names by reading bigger csv-files
Using pandas version of newest anaconda windows setup-installer:
pd.__version__
Out[11]: '0.25.1'

While importing larger csv-files there occures a shift in column names. 
Simple version works:
```
df = pd.read_csv(relpath + "\data.csv", sep=';', header=0,  
                  skiprows=[1], parse_dates=False, keep_date_col=True)

df.head()
Out[4]: 
          Timestamp  PMaxEVU  U_L1_L2  Frequency
0  01.12.2019 00:01    100.0   20.688     49.965
1  01.12.2019 00:02    100.0   20.704     49.947
2  01.12.2019 00:03    100.0   20.700     49.971
3  01.12.2019 00:04    100.0   20.701     49.988
4  01.12.2019 00:05    100.0   20.701     49.986
```
while normal mode leads to shift (see Timestamp has PMaxEVU-values)

```
df1 = pd.read_csv(relpath + "\ALL_DATA_01.csv", sep=';', header=0,  
                  skiprows=[1], parse_dates=False, keep_date_col=True)
df1 = df1.set_index('Timestamp')

df1.head()
Out[9]: 
           PMaxEVU  PMaxEVU_Active  CosPhi_OP  ...   ER  ER_Cap  Unnamed: 59
Timestamp                                      ...                          
100.0          0.0           -0.01     -100.0  ...  0.0     0.0          NaN
100.0          0.0           -0.01     -100.0  ...  0.0     0.0          NaN
100.0          0.0           -0.01     -100.0  ...  0.0     0.0          NaN
100.0          0.0           -0.01     -100.0  ...  0.0     0.0          NaN
100.0          0.0           -0.01     -100.0  ...  0.0     0.0          NaN

[5 rows x 59 columns]
```
this occures even with direct importing with parse_dates=True, 
```
df1 = pd.read_csv( relpath + "\ALL_DATA_01.csv", sep=';', header=0, 
                  index_col=0, skiprows=[1], parse_dates=True, 
                  keep_date_col=False)
```
Useing string name leads to KeyError - this may be an error on my side
```
df1 = pd.read_csv( relpath + "\ALL_DATA_01.csv", sep=';', header=0, 
                  index_col='Timestamp', skiprows=[1], parse_dates=True, 
                  keep_date_col=False)
```
```

  File "C:\ProgramData\Anaconda3\lib\site-packages\pandas\io\parsers.py", line 2100, in read
    values = data.pop(self.index_col[i])

KeyError: 'Timestamp'
```