The test point assembly device is a mechanical connection device, designed to be inserted in series with the rack mounted plug couplers. Each connection within the plug coupler shall provide a test point to allow voltage
measurement, and shall also be capable of being disconnected individually. Contacts and blocks shall be
arranged is such fashion that no adjacent circuits may be shorted by loosening or removal of the captive
fastener.
In general the test point assembly device shall meet the following criteria:
• Constructed using a fail-safe principle to exclude the possibility of a cross or short within the units that
could compromise the safety of the vital circuits.
• Be able to be "keyed" to match the keying in the plug AMP connector assemblies and to be able to be locked in-place.
• Incorporate test points on the outside of the assembly accessible for a maintainer to insert a test probe.
• Incorporate identification or numbers marked on the outside of the assembly corresponding to the plug connector pin numbering or circuit nomenclature.
• Allow for the disconnect of an individual circuit within the plug connector assembly without disconnecting the entire plug connector.
•  Meet all applicable AREMA requirements for fail-safe design, EMI/EMC and environmental requirements for temperature and vibrations based on actual laboratory testing.
• Design the test point assembly to accept 50-way and 28-way plug connector assemblies. (male and female)