CR:270 Series User Manual
Page 20
Peak is fitted
IEC 804 11.2.9 & IEC 651 11.2.7
The effect of vibrations is such that 5g in any direction will not cause a reading on
scale.
IEC 804 11.2.10 & IEC 651 11.2.8
The unit is unaffected by a field of 80 A/m
IEC 804 11.2.11 & IEC 651 11.2.9
The unit remains within specification at any temperature between -10 and +50 degrees
Celsius. It may be stored safely between -20 and +70 degrees Celsius.
IEC 651 11.2.10
The operators must remove themselves from the measuring field by putting the unit on
a tripod. However, if this is not possible the unit will meet Type 2 specifications when
held at arms length.
IEC 804 11.2.12 & IEC 651 11.2.11
The unit will meet its specification at any humidity from 0 to 99 % RH.
IEC 804 11.2.13 & IEC 651 11.2.12
Maximum storage temperature of +60 degree (+50 degree extended period) and 50%
RH should be observed.
IEC 804 11.2.14 & IEC 651 11.2.13
There is no provision for a microphone extension cable on the standard CR:272 &
CR:274 units. However, if an extension cable option is in use with the CR:271 or
CR:273 units, C irrus Research cables up to 10 meters long will not affect the
calibration.
IEC 804 11.2.15 & IEC 651 11.2.14
The UA:237 windscreen has negligible effect on calibration up to 12.5kHz.
IEC 804 11.2.16 & IEC 651 11.2.15
The use of a pistonphone (PF 101B) is required to ensure long term compliance. For
short term compliance the CR:513A may be used but this should be checked against a
secondary or transfer standard annually.
IEC 804 11.2.17 & IEC 651 11.2.16
The observer should be behind the case for optimum results. The operator should
never be at the side or in front of the unit.
IEC 804 11.2.18 & IEC 651 11.2.17
Not applicable.
IEC 804 11.2.19 & IEC 651 11.2.18
The limitations on the electrical impedance that may be connected to the output
connectors:- Any real, positive impedance of zero ohm upwards.
IEC 804 11.2.6 & IEC 651 11.2.19
The reference frequency used for calibration is 1kHz.
IEC 804 11.2.8 & IEC 651 11.2.20
The reference range for IEC 651 purposes is centre range.
