Thyristor valve is one of the key equipments for ultra high voltage direct current(UHVDC) power transmission projects.Before being installed on site

they need to be tested in a laboratory in order to verify their operational performance to satisfy the technical specification of project related.Test facilities for operational tests of thyristor valves are supposed to enable to undertake more severe electrical stresses than those being applied in the thyristor valves under test(test objects).On the other hand

the stresses applied into the test objects are neither higher nor lower than specified by the specification

because inappropriate stresses applied would result in incorrect evaluation of performance on the test objects

more seriously

would cuase the damage of test objects with expensive cost losing.Generally

the process of operational tests is complicated and performed in a complex synthetic test circuit(hereafter as STC)

where there are a lot of sensors used for measuring

monitoring and protection on line to ensure that the test circuit functions in good condition.Therefore

the measuring systems embedded play a core role in STC

acting like "eyes".Based on the first project of building up a STC in China

experience of planning measuring systems is summarized so as to be referenced by related engineers.