Product Description:CYJB Series microcomputer relay protection tester is a new small microcomputer relay protection testing instrument, manufactured referencing DL/T624-199"microcomputer relay protection test device technology", listening to the views of users, summarizing. Product Description:CYJB Series microcomputer relay protection tester is a new small microcomputer relay protection testing instrument, manufactured referencing DL/T624-199"microcomputer relay protection test device technology", listening to the views of users, summarizing. Relay protection is an important measure for detecting faults or abnormal conditions in a power system so as to send out alarm signals or directly isolate and cut off fault parts, relay protection is an automatic measure for preventing accidents in the power system, and main protection objects. The Protection Relays product portfolio includes relay test equipment that are designed to test current pickup level, time-delay, and coordination of ground-fault protection. These ground-fault relay test units are used on substations, motor control centers, central distribution panels. Compact relay test set for quick and easy manual three-phase testing Ultra-portable test set for primary and secondary injection, as well as basic protection tests Modular, multi-phase protection relay test set and commissioning tool Compact relay test set for quick and easy manual three-phase. The following set of instructions will help you to operate the demonstration unit for AC Contactors and AC DC Relays with ease. Variable AC Voltage Source 0 - 250 V / 4 Amp. with Isolation Transformer having Tapping 0-50 V, 0-100 V, 0-250 V ( Tapping will be selected with switch). If you have any questions or you'd like to discuss a.