I think it would be best to use the classic chart (which is the next one in the charts tab from the easy chart). It has a property called Data that you can bind to a SQL query. All you must do is make sure the timestamp column is returned as the first column in a time series chart.
You can do it with the Easy Chart as well but you have to create DB pens with dynamic where clauses (like Nathan said). For example, you can create a DB pen where you specify which column is the data column and which column is the timestamp column. Let it know which table to grab the information from which is ht_cm1 in your case. You can go to the dynamic groups tab in the customizer and add one for each shift. That will add three dynamic properties to the chart for the where clause. You can bind each one to an expression that returns:
date_format(curdate(),’%d-%m-%Y’)=date_format(t_stamp,’%d-%m-%Y’) and date_format(t_stamp,’%T’)<‘08:00:00’
for Shift 1 example. Hope this helps.