Tempest AT5K Resistance Tester

The Tempest AT5K™ Resistance Tester is a compact maintenance tool for checking internal resistance in aviation spark plugs. It provides a quick LED indication to support spark plug resistance checks during maintenance and inspection activities.

• Manufacturer part number: AT5K
• Green LED: resistance below approximately 4 kΩ.
• Green and red LEDs: resistance below approximately 5 kΩ, identified by Tempest as a serviceable range.
• Red LED only: resistance above approximately 5 kΩ.
• Designed to check resistance values only; it is not a substitute for other required spark plug condition assessments.
• Tempest documentation states that the AT5K can be used with popular aviation spark plugs, including shielded and unshielded types when used in accordance with the instructions.

For operation, place the spark plug barrel over the tester contact post and touch the test lead to the centre-electrode firing end. Refer to the manufacturer’s AT5K Spark Plug Resistance Tester Instructions for operating, calibration and care guidance.