CR:270 Series User Manual
Page 19
Rating Plate Information
The CR:27x meets IEC 651 (BS EN 60651) and IEC804 (BS EN 60804) Types 1 or 2,
depending on the microphone fitted. The specifications IEC 651 and IEC 804 require
that this manual provides detailed information to verify that the specifications are met.
While much of the data required is in the body of this manual, the points required to be
detailed are listed below in the order in which they occur in the IEC specification. The
numbers marked after to IEC number refer to that documents paragraph numbers for
reference.
IEC 804/651 11.2.1
The microphone is an electret condenser microphone mounted on the case. To meet
IEC Type 1 or 2 the unit should be fitted on a tripod.
IEC 804/651 11.2.2
The reference direction of incidence is parallel to the case as marked with an arrow on
the cone.
IEC 804/651 11.2.3
The range of measurement for Leq and SPL measurement with a standard assembly is:-
CR:272 & CR:274 : 32 to 140 dB(A)
: 50 to 140 dB(C)
CR:271 & CR:273 : 27 to 140 dB(A)
: 47 to 140 dB(C)
The range of measurement for Peak measurement with a standard assembly is:-
CR:272 & CR:274 : 60 to 143 dB(C)
CR:271 & CR:273 : 60 to 143 dB(C)
IEC 804 11.2.4
Linearity and pulse range
CR:272 & CR:274 Low Range
45dB to 80dB (83dB peak)
Mid Range
55dB to 110dB (113dB peak)
High Range
85dB to 140dB (143dB peak)
CR:271 & CR:273 Low Range
35dB to 80dB (83dB peak)
Mid Range
50dB to 110dB (113dB peak)
High Range
80dB to 140dB (143dB peak)
IEC 804 11.2.7 & IEC 651 11.2.4
The reference sound pressure is 1 Pa (94dB).
IEC 804 11.2.5
The integration period is the period between resets.
IEC 651 11.2.5
'A' and 'C' weightings are provided.
Peak is displayed in dB(C) only.
IEC 651 11.2.6
"F", "S" and "I" responses are fitted with a 'Hold' on the max RMS value of each.
