The PRIMUS Pri-Matic® control system’s first three cycle recipes (i.e., the cycle parameter data) are programmed during the PRIMUS Factory Acceptance Test (FAT). There are numerous parameters that can be set to allow the Pri-Matic® controls to support virtually any sterilization requirement.

These three cycles will be immediately available to the end user when the sterilizer is installed. The end user is responsible for programming any additional cycle recipes to meet their specific needs (or reprogramming values for the three cycles already present).

Three Factory Programmed Cycles

The three named cycles are:

  • HARDGOODS (Uses a Gravity Cycle)
  • LIQUIDS (Uses a Liquid Cycle)
  • WRAPPED GOODS (Uses a Vacuum Cycle)

They are programmed into the controller as Cycles 1, 2, and 3, respectively, and are used to test the sterilizer as part of the standard PRIMUS FAT protocol.

Unlike the PSS5 and the PSS8 Trinity controls, the PSS9 Pri-Matic® controls do not have a factory reset function for the cycle recipes.

Programming Flexibility

Due to the flexibility of the controls, it is easy to end up with significant variances in the parameter settings based on the load type, the facility requirements and the size of the sterilizer.

The facility should always print out their cycle data for reference and keep it somewhere easily accessible before changing any values.

In some instances, the facility may wish to restore the cycle data to the factory standard, especially if incorrect values have been accidentally saved.

The following tables show the standard values entered into the controls as recipes during the PRIMUS FAT:


Some of the available values will not apply to every sterilizer. For example, if the Air Over option was not purchased for a sterilizer, then the Air Over parameter settings will have no function. Also, due to the sterilizer chamber size, there may be some minor differences in the factory values and the tables listed below.

Improperly setting values can cause unanticipated results!

As an example, if the sterilizer is not equipped with a Load Probe, then telling the sterilizer to use the Af0 settings will not work to control the end of the sterilization phase. If the cycle was set to use Af0 rather than Time as the end condition for a run, then the sterilizer will remain in the Sterilize phase waiting indefinitely for the Af0 setpoint, as reported by the Load Probe, to be reached. This will never happen. Therefore, with no Load Probe, the ST END setting should always be set for 0 (Time).

Creating New Cycles

An easy way to create new cycles is by copying PSS9 Cycle Parameters.



Table 1 Standard Cycle Parameters

[Table 1: Pages 3-6]

Table 2 Global and Special Parameters

[Table 2: Page 7]

Have a question or having difficulties? Talk to Dave Schall, our PRIMUS sterilizer expert who is here to assist you anytime at 877.679.7800 extension 1212 or email at

Visit us at

Back to Blog