Prostat Corporation | ESD Blog

The Prostat PRS-801 is a portable, battery operated resistance meter, capable of measuring from less than 1 ohm to 2.0E+14. It could be challenging to make low resistance and high resistance measurements, and below are some tips to help accomplish these tasks.

Before plugging cables or low resistance reference into the terminals:

1. Slide the Battery Bus switch ON
2. Press the Red ON/OFF button to energize the unit
3. Press Green TEST button after the self-test is complete
   • Confirm the instrument goes to OL without leads connected
   • Press the Yellow RESET button
   • Repeat a. & b. above several times to warm the system
   • Allow the unit to sit energized for a least 3 minutes.
     NOTE: Ideally, the PRS-801 should have a minimum of 3 to 5 minutes of warm-up time before taking precision measurements and calibrating the low resistance range.
   • Press the Red ON/OFF button to de-energize the instrument

For Very Low Resistance i.e., less than 10 Ohms and other Measurements,

1. Insert the low resistance calibration module into the terminals
2. Press the ON/OFF button to energize the system
3. Press the CLEAR button one time to enter CAL mode
4. Press the Yellow RESET button to adjust the instrument low resistance range
5. Press Green TEST; display should show 1.02 Ohms, ±0.02 Ohms.
6. To repeat the calibration process, press RESET then CLEAR within one-half second to re-enter the low resistance CAL mode and repeat steps 4 & 5 above.
7. Press the Red ON/OFF button to de-energize the instrument
8. Insert test leads
   NOTE: If the unit is ON and test lead insulation is charged when connected to the device, an electrostatic discharge (ESD) will be delivered to the instrument’s circuitry causing the instrument to turn OFF, or re-start. This response to the ESD event is the instrument’s response for its own protection.
9. Press Red ON/OFF button to energize the instrument and conduct measurements.

Additional Tips For High Resistance measurements 1.0E11 Ohms and higher

1. Use short, shielded test leads supplied with the PRS-801
   • Be sure to insert the Black lead into the negative (-) terminal
   • The Green Shield should be inserted in the instrument’s ground reference
   • The Red test lead should be inserted into the positive (+) terminal
   • The operator must be grounded to an approved ESD personnel ground
   • Once the leads are connected to the fixture or object being measured, press the Red ON/OFF button to energize the system
   • Press the Green TEST button to initiate the measurement
     NOTE: The electrification period for measurements 1.0E12 Ohms and greater, the electrification period is automatically extended to 15 seconds, plus any additional time required to obtain a reasonable measurement
2. IMPORTANT for High resistance measurements: The grounded Operator should step back, away from the instrument and test fixture to prevent body capacitance and fields from clothing or the body from interfering with the measurement.
3. Once HOLD is displayed, the measurement is complete; press the Yellow RESET button to enter the data into memory or to simply prepare the instrument for the next measurement.