Standard ASTM F1207-89
1.1 This specification covers electrical insulation monitoring devices, intended as permanently installed units, for use in the detection of ohmic insulation faults to ground in active, a-c ungrounded electrical systems.
1.2 Limitations -This specification does not cover devices which are not intended for operation for: d-c ungrounded systems or a-c ungrounded systems with d-c components unless a-c to d-c conversion is isolated from the monitored system with transformers.
1.3 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
1.4 The following precautionary caveat pertains only to the test methods portion, Section 9, of this specification: This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety problems associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.