This standard is prepared in accordance with Notzjication on the development and revision plan of the secondbatch energy industrial standards in 2011 issued by National Energy Administration [GNKJ （2011）No.252].

This standard is structured and organized in accordance with Standard GB/T 1.1-2009 Directives for standardization-Part 1： Structure and drafting of standards.

The standard is a revision to standard DL/T 507-2002 Start-up test code for hydro-generating units （hereinafter referred to as the previous standard）. Compared with the previous standard， the main technical changes include：

——Revised the limit on run-out （peak-to-peak value） for unit operation.

——Revised allowable values of horizontal and vertical vibration （peak-to-peak value） of turbine head cover with rated speed greater than 375 rpm to 750 rpm and allowable value of horizontal vibration （peak-to-peak value） of the frame at stator core， and added explanation on the characteristics of allowable values.

——Explained in details the parameter adjustment test for service water supply； and explained in details the short-circuit test for station service transformer by means ofhydro-generating units.

——Added test on injection-type ground protection of hydro-generating units.

——Revised loading and load shedding test of hydro-generating units； and added test on thermal stability of hydro-generating units.

——Clarified requirements for test on dynamic water closing service gate or inlet valve of turbine and test on closing ring gate ofhydro-generating units.

——Added requirements on simultaneous'load shedding test of multiple generating units that share a single waterway.

——Cancelled the requirement for 30-day comnussioning.