In Power Compensation mode, the aim is to keep the temperature difference between the sample and reference sides as close to zero as possible.
On the MMS 1 DSC sensor, this is achieved by two local heaters, one below the sample crucible and one below the reference crucible.
The temperature difference between the sample and reference (ΔT) is zero as long as there is no thermal effect in the sample. A thermal effect will cause the sample temperature to deviate from the reference temperature.
For example, with an exothermic effect such as crystallization, the sample releases energy and becomes warmer than the reference. The heater on the reference side will then activate, increasing the reference temperature until it matches the sample temperature (ΔT = 0).
When there is an endothermic effect such as melting, the sample becomes cooler than the reference. The sample heater will then activate, increasing the sample temperature until it matches the reference temperature.