Micom P721, Technical Manual

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Handling, Installation and Case Dimensions P72x/EN IN/C21
MiCOM P721/P723 Page 3/10
1. GENERAL CONSIDERATIONS
BEFORE CARRYING OUT ANY WORK ON THE EQUIPMENT, THE
USER SHOULD BE FAMILIAR WITH THE CONTENTS OF THE SAFETY
GUIDE SFTY/4LM/E11 OR LATER ISSUE, OR THE SAFETY AND
TECHNICAL DATA SECTIONS OF THE TECHNICAL MANUAL AND
ALSO THE RATINGS ON THE EQUIPMENT RATING LABEL.
1.1 Receipt of relays
Protective relays, although generally of robust construction, require careful treatment prior to
installation on site. Upon receipt, relays should be examined immediately to ensure no
damage has been sustained in transit. If damage has been sustained during transit a claim
should be made to the transport contractor and Schneider Electric should be promptly
notified.
Relays that are supplied unmounted and not intended to be installed immediately should be
returned with their protective polythene bags.
1.2 Electrostatic discharge (ESD)
The relays use components that are sensitive to electrostatic discharges.
The electronic circuits are well protected by the metal case and the internal module should
not be withdrawn unnecessarily. When handling the module outside its case, care should be
taken to avoid contact with components and electrical connections. If removed from the case
for storage, the module should be placed in an electrically conducting antistatic bag.
There are no setting adjustments within the module and it is advised that it is not
unnecessarily disassembled. Although the printed circuit boards are plugged together, the
connectors are a manufacturing aid and not intended for frequent dismantling; in fact
considerable effort may be required to separate them. Touching the printed circuit board
should be avoided, since complementary metal oxide semiconductors (CMOS) are used,
which can be damaged by static electricity discharged from the body.