Blue-Ray Biotech Support-Technology

Thermal Cycler

  • Introduction to Peltier device

While in some old PCR machines the block is submerged in an oil bath to control temperature, in modern PCR machines a Peltier element is commonly used.

A Peltier element is a solid-state active heat pump which transfers heat from one side of the device to the other, with consumption of electrical energy, depending on the direction of the current. Such an instrument is also called a Peltier device, Peltier heat pump, solid state refrigerator, or thermoelectric cooler (TEC). It can be used either for heating or for cooling.

  • Block Mode vs Sample Mode
  • Block Mode: Enables system operation with maximum temperature control based on the actual block temperature regardless the sample temperature. This mode is design to mimic the control algorithm of the early day thermal cyclers.


  • Sample Mode: Enables system operation with simulated temperature control. Users are required to input the sample volume. In this mode, temperature control algorithm will estimate sample temperature based on the block temperature as well as the sample volume. Recommended for normal operation.

Block Mode vs Sample Mode