Challenge Test For Metal Detectors

Metal Detector Challenge Test

Metal detectors are used at tablet compression & capsule filling stages. The basic purpose of metal detectors is to remove any tablet or capsules that may contain any metal piece.

Why To Perform Challenge Tests

We have to challenge the working of metal detectors to ensure that they are efficient and capable of removing any metal-containing tablets or capsules.

Test Kit/Tablets For Challenge Test

We use various types of metals to challenge the working of metal detectors. These metals are provided by the vendor in the form of tablets.

The following types of metal-containing tablets are provided for the challenge test 

  • Nickel Containing Tablet
  • Ferrous Containing Tablet
  • Brass (Non-ferrous) Containing Tablet
  • SS-containing Tablets 
  • Dummy Tablet

The above-mentioned test tablets are manufactured by Food grade material & metal pieces are trapped inside these food-grade tablets. Generally, these tablets are available in various colors for identification.


These may vary depending on the sensitivity of the metal detector.

How To Perform Challenge Test 

We pass all the tablets one by one through the metal detectors to check their sensitivity & working.

First of all, take the Nickel-containing tablet and pass it through the metal detector. It must be rejected by the metal detector. If it is rejected it means the metal detector working is efficient for Nickel-containing tablets.

Now take bras containing tablet & pass it through the metal detector. If it is rejected it means the metal detector working is efficient.

Now pass ferrous-containing tablets & it must also be rejected by the metal detector.

Now pass the SS-containing tablet from the metal detector & it must be rejected.

Now pass the dummy tablet. A dummy tablet contains no metal so the metal detector should not reject it.


If any of the above-mentioned metal-containing tablets are not rejected by the metal detector it means that there is a malfunction in the sensitivity & working of the metal detector.

Send a request to the engineering department for rectification & again perform a challenge test after rectification to check it is working.

If all the tests performed are passed then use this metal detector for compression operation.

Frequency Of Challenge Test

The frequency of challenge test is defined by the in-house standard operating procedure & may be as follows

  • Before starting the compression process
  • After major breakdown 

Also Read 

  1. Metal Detector Working
  2. Stages and Mechanism of Tablet Compression.
  3. Advancements in tablet compression machines.
  4. Calculation of compression machine capacity.