3M Workstation Monitor 724, Руководство пользователя

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9
Audible Alarm Tones
For wrist strap malfunctions the 3M
™
Workstation Monitor 724 indicates a different
tone for each operator – a continuous tone for
#1 operator and a fast chirping beep for #2
operator. The volume of the wrist strap alarm
is adjusted by selection of the internal DIP
switch #1. For work surface malfunctions, a
slow chirping beep is made. This alarm sound
is turned on or off by selection of DIP switch
#2. Switch #1 and #2 are accessible through a
slot located in the bottom of the chassis.
Work Surface Monitoring
The Workstation Monitor 724 monitors its connection
to ground and the grounding of a 3M ESD work
surface. A loop resistance is measured from the
monitor, through a 3M
™
Monitor/Table Mat Cord
2380D to the work surface (Section 2), across the
conductive layer of the work surface, through the
grounding wire of the work surface to an electrical
ground and finally back to the monitor through the
Workstation Monitor 724 grounding wire. If the
resistance of the loop exceeds 3.7 Megohms the work
surface high red lamp (M) will illuminate and all
green lamps will be extinguished. If DIP switch
#2 is in the ON position (Figure 4) the audible
alarm will activate. If no ESD work surface is to be
monitored, the Monitor/Table Mat Cord 2380D and
the ground wire of the Workstation Monitor 724
must be connected to an electrical ground (Section
3). This is done to ensure that the Workstation
Monitor 724 is providing a ground connection for
the operators. Again, if the loop resistance exceeds
3.7 Megohms the work surface high red lamp
(M) will illuminate and the alarm will activate
if selected. 2380 Mat Cord (without resistor) can also be used with the 724
Workstation Monitor It can be used when the surface resistance threshold of 3.7
Megohms is reached using the 2380D.
Loud
Soft
Model 724 bottom view
On
Off
DIP switch
Switch #2
Switch #1
Figure 4 – Selected desired alarm options
NOTICE
The grounding wire from the
work surface and the ground
wire from the 3M
™
Workstation
Monitor 724 must be attached to
separate electrical grounds. The
work surface monitoring function
is active any time that the power
supply for the monitor is plugged in.
NOTICE
Disconnect the 3M
™
Monitor/
Table Mat Cord 2380D to prevent
possible damage to the 3M
™
Workstation Monitor 724 before
testing the resistance of the
work surface with a high voltage
megohmmeter.
3M
™
Workstation Monitor 724 bottom view