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OFFSET COMPENSATION:
1. Switch the instrument into the measure model.
2. After approximately three minutes. The instrument should indicate 0000 on the digital panel
meter. An offset of 5-7
μ
Sv/hr is typical for situations due to temperature changes. This offset
should disappear as thermal equilibrium is attained.
3. Adjust the “offset” compensation potentiometer as required. The location is shown in Figure 1.
NOTE:
The rotation direction for the adjustment is clockwise for change in a
positive direction. Use very small amounts of rotation, the display will not
react immediately because there is a 30 second time constant.
GENERAL
OPERATION
NOTES:
The following information is provided to the user to ensure stable and accurate performance.
The monitor can be located on any flat surface, such as a table top, or, it can be mounted to a wall
bracket or shelf, or on a small moveable cart. In all cases, the instrument must be protected
against vibration, shock, moisture and dirt.
ELECTRICAL GROUNDING
The electrical and electronic equipment grounding is often considered only from the viewpoint of
hazard and safety. Indiscriminate or excessive grounding may actually enhance the potential of
danger and disturb the proper internal operation of the instrument. The electronic circuitry,
including logic, adjustment controls, local and remote displays, are centrally and all inclusively
grounded at the ionization chamber module. The circuit system common line is electrically
connected to the metal frame or housing of the electrometer module. When signal outputs are
connected to remote displays, computer interfaces, or similar devices, it is necessary that no
significant ground potential differences exist between the monitor and other equipment. If
significant potential ac or dc differences exist, shifts in the instrument “zero” can appear.
THE FOLLOWING IS RECOMMENDED
1. Make all interconnections. Normally the instrument operates on (2) “D” cell batteries. If it is
desired, the instrument can operate continuously by connecting to the AC power converter
provided. Use only the AC converter that is provided. Activate the instrument. Allow ten
minutes “warm-up”. Adjust zero if needed.
2. Attach remote connections (devices) and verify absence of change in zero.
If zero has changed, check for ground loops and spurious ac or dc potential differences from one
location to the other.
NOT SUITABLE FOR USE IN WET LOCATIONS
NOT SUITABLE FOR USE IN EXPLOSION HAZARD ENVIRONMENTS