How should two datasets be compared?

[DOptimusPrime]

I'm`` trying to compare these two dataset and select the corresponding timesteps from another set. The documentation say that "==" can be used for element-wise comparison. https://docs.xarray.dev/en/stable/generated/xarray.Dataset.equals.html. But it seems not to be working is there a do a better comparison

kelvin["Time"] == freeze_rain["Time"]).all()` seem not to be the right approach. 
`qrain= xr.open_mfdataset("\Q_RAIN*.nc")
temperature= xr.open_mfdataset("\T_2*.nc").resample(Time="3H").mean()
prec= xr.open_mfdataset("\Precipitation*").resample(Time="3H").mean()
print(temperature.dims)
print(prec.dims)
t2= temperature
muscatine = qrain
freeze_rain= muscatine.where(muscatine["QRAIN"].compute() >0, drop= True)
kelvin_mask = (t2["T2"] < 273).compute()
station_names = ["Muscatine", "Algona", "Cedar Falls", "Pella"]
kelvin = t2.where(kelvin_mask, drop=True)
common_times = prec.where((kelvin["Time"] == freeze_rain["Time"]).all(), other= 0)

common_times seems not to be returning the right output.