Electrostatic Discharge (Esd) - Curtis 1353 User Manual

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ELECTROSTATIC DISCHARGE (ESD)

Curtis products, like most modern electronic devices, contain ESD-sensitive components, and it is
therefore necessary to protect them from ESD (electrostatic discharge) damage. Most of the product's
signal connections have protection for moderate ESD events, but must be protected from damage if
higher levels exist in a particular application.
ESD immunity is achieved either by providing sufficient distance between conductors and the ESD
source so that a discharge will not occur, or by providing an intentional path for the discharge current
such that the circuit is isolated from the electric and magnetic fields produced by the discharge. In
general the guidelines presented above for increasing radiated immunity will also provide increased
ESD immunity.
It is usually easier to prevent the discharge from occurring than to divert the current path. A fundamental
technique for ESD prevention is to provide adequately thick insulation between all metal conductors
and the outside environment so that the voltage gradient does not exceed the threshold required for a
discharge to occur. If the current diversion approach is used, all exposed metal components must be
grounded. The shielded enclosure, if properly grounded, can be used to divert the discharge current; it
should be noted that the location of holes and seams can have a significant impact on ESD suppression.
If the enclosure is not grounded, the path of the discharge current becomes more complex and less
predictable, especially if holes and seams are involved. Some experimentation may be required to
optimize the selection and placement of holes, wires, and grounding paths. Careful attention must
be paid to the control panel design so that it can tolerate a static discharge. MOV, transorbs, or other
devices can be placed between B- and offending wires, plates, and touch points if ESD shock cannot
be otherwise avoided.
APPENDIX A
Curtis 1353 CANopen Expansion Module Manual – June 2017
pg. 49