Caution
The Model 725 Monitor does not have the capability of verifying that the ground point is a suitable ground. If you are not sure what a suitable ground is, contact a licensed electrician before installation.
The Model 725 Monitor requires only a small amount of current to operate. When the red lamp and the audible alarm are activated simultaneously the monitor requires approximately 5 µA of current. When the lamp and alarm are not activated (normal condition) the monitor requires approximately 50 ∝A of current.
As with any battery operated electronic device, the life of the battery will be determined by the frequency of use. However, for the Model 725 Monitor you can expect a battery life of approximately one year in continuous operation under normal conditions.
Note:
Use an alkaline battery for longer life.
The Model 725 monitors the battery voltage and alerts the operator when it is necessary to change the battery. When the battery voltage falls below 6 volts the red lamp will illuminate with no audible alarm. At this time the Model 725 is still operational, making reliable resistance measurements
of the wrist strap assembly and the ground connection.
Voltage on Operator when Connected to the Model 725 Monitor
There is a concern about the voltage that is applied to an operator while they are connected to a monitor. Some of today’s electronic components are extremely sensitive
to electrostatic discharge from a person (less than 10 volts). The following chart for the Model 725 Monitor illustrates the level of voltage that will appear on the operator under various resistance conditions.
Voltage on Operator When Connected to the Model 725 Monitor
Condition | Observed Voltage |
No Skin Resistance | 0.8V |
200K Ohm Skin Resistance | 0.9V |
Likely Case Before Alarm | 3.5V |
Worst Case Before Alarm | 6.8V |
Absolute Worst Case | 9.0V |
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