Fluke Biomedical 956A-201-M2 - Manual (Page 42)

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5. Refer to Table 3-4 for a listing of function switch setpoint descriptions.
6. The firmware in the UDR checks alarm, and analog range setpoints for invalid conditions, and will not
accept an invalid setpoint (i.e. Warn alarm greater than High alarm, High alarm less than Warn alarm)
as defined in Setpoint Descriptions, Section 3.8. After a setpoint has been changed, the operator
must re-display the setpoint, to verify the new setpoint has been accepted.
7. During setpoint entry, the bar graph and analog outputs function normally. Once the setpoint is
entered, the impact of the changed value, if any, will be seen.
3.9 SETPOINT DESCRIPTIONS
High Alarm Limit, Setpoint 0
This setpoint is entered in units of mR/h in the exponential format X.XXEN. The high alarm limit setpoint
can be set to any value desired. When the display value exceeds this limit, the UDR will go into a HIGH
alarm state. The HIGH alarm limit must be greater than or equal to the WARN alarm and the underrange
limit. It must be less than or equal to the overrange limit.
Warn Alarm Limit, Setpoint 1
This setpoint is entered in units of mR/h in the exponential format X.XXEN. The warn alarm limit setpoint
can be set to any value desired, but must be lower than the high alarm limit setpoint. When the displayed
value exceeds this limit, the UDR will go into a WARN alarm state. The WARN alarm limit must be greater
than or equal to the low scale value and less than or equal to the HIGH alarm limit.
Resolving Time (Dead Time), Setpoint 2
This setpoint is entered in units of minutes per count. The actual value to be entered is a function of the
individual detector and is stated on the calibration data sheet supplied with the detector. If a complete
system is purchased (i.e. 955A-100), this setpoint is entered at the factory.
Analog Full Scale Value, Setpoint 3
This value is the dose rate at which the analog output is set to full scale (i.e. 10 volts or 20 mA). This
value must be an even power of 10 that is at least 1 decade higher than the analog low scale value. An
even power of 10 is a number of the form 1.00EX, where E indicates a positive exponent, a (-) sign
indicates a negative exponent, and X equals a number between 0 and 9. This parameter is entered in
units of mR/h and sets the upper value of the analog outputs. This value must be set to exact decade
values. Example: 1.00E4 is acceptable, 2.00E4 is not. A setpoint that is other than 1.0 will not be
accepted by the UDR. If the analog Full Scale value is equal to the Low Scale Value, Error Code E0008 is
displayed. If the Full Scale Value is less than the Low Scale Value, the setpoint is not accepted.
Overrange, Setpoint 4
This setpoint is entered in units of mR/h. It is normally set for the upper limit value of the detector used
(for the 897A-21 0 it is 1.00E3, for the 897A-220 it is 1.00E4, and for the 897A-230 it is 1.00E5). When the
measured radiation value exceeds this setpoint, the unit goes into a range alarm state. The overrange
limit must be greater than or equal to the HIGH or WARN setpoints.
Conversion Constant, Setpoint 5
This setpoint is a detector dependent value that is used to convert the detector output, counts per minute
(CPM) to mR/h. The actual value to be entered is stated on the detector calibration data sheet. The units
are mR/h per counts per minute. If a complete system is purchased (i.e. 955A-100), this setpoint is
entered at the factory.