Foreword - Parker H Series Installation & Service Instructions Manual

Safety Guidelines for the Application, Installation and Maintenance of Solid State Control

Foreword

This Parker Hannifin Corporation publication is formatted to harmonize with NEMA Standards Publication No. ICS 1.1-1987, also titled
Safety Guidelines for the Application, Installation and Maintenance of Solid State Control. The text of the NEMA Standard has been
reprinted verbatim, with NEMA's permission, in the left column, captioned "NEMA Standard Text". The right column, captioned
"Explanatory Information", contains additional comments. The comments provide supplementary information to the NEMA Standard to
help the reader better understand the characteristics of industrial equipment employing solid state technology.
NEMA Standards Publication No. ICS 1.1-1984, Rev. No. 1 – October 1987, is available from the National Electrical Manufacturers
Association, 2101 L Street, N.W., Washington, D.C. 20037.
NEMA Standard Text
SCOPE – This Standards Publication is intended to provide
general guidelines for the application, installation, and
maintenance of solid state control in the form of individual
devices or packaged assemblies incorporating solid state
components. The emphasis of the guidelines is personnel
safety. Applicable NEMA standards and product related
instructions should be carefully followed.
Section 1
Definitions
Electrical Noise – Unwanted electrical energy that has
the possibility of producing undesirable effects in the
control, its circuits and system. Electrical noise includes
Electromagnetic Interference (EMI) and Radio Frequency
Interference (RFI).
Electrical Noise Immunity – The extent to which the
control is protected from a stated electrical noise.
Electromagnetic Interference (EMI) – Electromagnetic
disturbance that manifests itself in performance degradation,
malfunction, or failure of electronic equipment. (IEC)
Off-State Current – The current that flows in a solid state
device in the off-state condition.
Off-State Condition – The conditions of a solid state
device when no control signal is applied.
On-State Condition – The condition of a solid state device
when conducting.
Radio Frequency Interference (RFI) – RFI is used
interchangeably with EMI. EMI is a later definition that
includes the entire electromagnetic spectrum, whereas RFI
is more restricted to the radio-frequency band, generally
considered to be between 10k and 10G Hz. (IEC)
Surge Current – A current exceeding the steady state
current for a short time duration, normally described by
its peak amplitude and time duration.
Transient Overvoltage – The peak voltage in excess of steady
state voltage for a short time during the transient conditions
(e.g., resulting from the operations of a switching device).
Explanatory Information
(Supplementary Comments – Not part of NEMA
STANDARDS PUBLICATION NO. ICS-1.1)
The scope of this Parker Hannifin Corporation Publication
(E116P) is identical to the scope of NEMA Standards
Publication No. ICS 1.1, quoted in the left column.
2
SCOPE
E116P