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The ratio, the purity, and the concentration of two enantiomers can be measured via polarimetry. Enantiomers are characterized by their property to rotate the plane of linear polarized light.
Live testing. Earth fault loop impedance testing: this test is to check that if a fault did occur, that the system meets requirements to cause a disconnection of the supply within the time limit specified by standards Insulation resistance testing Polarity test: a test to check that the connections are connected in the right sequence
In countries where the sockets are polarised, polarity testing is a simple test that can be carried out using a polarity tester to determine whether the line and neutral of the plug end are correctly connected to the corresponding terminals at the socket end. [11] [12]
A receptacle tester being used to check for some types of improper wiring of an outlet. For this particular tester, proper wiring is indicated by the two yellow lights. The outlet tester checks that each contact in the outlet appears to be connected to the correct wire in the building's electrical wiring. It can identify several common wiring ...
Auto-polarity for direct-current readings, shows if the electric polarity of applied voltage is positive (agrees with meter lead labels) or negative (opposite polarity to meter leads). Sample and hold, which will latch the most recent reading for examination after the instrument is removed from the circuit under test.
Pole mounted distribution transformers are manufactured with additive polarity, while instrument transformers are made with subtractive polarity. Where markings have been obscured or are suspect, a test can be made by interconnecting the windings and exciting the transformer, and measuring the voltages. [4]
Automated optical inspection (AOI) is an automated visual inspection of printed circuit board (PCB) (or LCD, transistor) manufacture where a camera autonomously scans the device under test for both catastrophic failure (e.g. missing component) and quality defects (e.g. fillet size or shape or component skew). It is commonly used in the ...
A common form of in-circuit testing uses a bed-of-nails tester.This is a fixture that uses an array of spring-loaded pins known as "pogo pins". When a printed circuit board is aligned with and pressed down onto the bed-of-nails tester, the pins make electrical contact with locations on the circuit board, allowing them to be used as test points for in-circuit testing.