SURFACE RESISTANCE CHECKER
The measurements of both surface resistivity and resistance to ground. Giving simple repeatable measurements of conductive, static dissipative and insulative surface. The checker employs the ASTM standard D-257 method of parallel bar sensing. Ranging is automatic due to the use of high speed OP-AMP integrated circuits being linear, with changeover points + or ?1/2 decade on a logarithmic scale ( 1 or 10% from mean value per unit).
Operation
Remove the battery compartment and panel and check that a good quality PP3 alkaline battery has been fitted. Hold the checker away form any surface and press the test button, the insulative red LED light.
Place the checker onto the surface that requires testing, again press the test button and hold. The LED that illuminates constantly is the decade measured.
10/3=1 kiohm Green LED 10/9 = 1,000 meg ohms Yellow LED
10/4=10kilohms Green LED 10/10=10,000megohms Yellow LED
10/5=100kilohms Green LED 10/11=100,000megohms Yellow LED
10/6=1megohm Yellow LED 10/12=1,000,000megohms Red LED
10/7=10megohms Yellow LED >10/12=Insulative Red LED
10/8=100megohms Yellow LED
Checking Resistance to ground
the ground/earth leakage lead the ground/earth leakage socket. This is lates the test probe ont the right side of the meter. (The same blue as the socket). Connect the croc clip to your ground connection.
Place the checker on to the surface to be tested, press and hold the test button. The LED that illuminates constantly is the decade measured. The
Measurement will be resistance to ground in ohms instead of ohms per square.
Calibration
The checker should be calibrated on average every 12 months. A test resistance can be applied across the parallel bars to verify if the checker is within specification, using a resistance decade box. Calibration can be obtained by contacting your supplier.
Specification
Power supply 9 volt PP3 alkaline battery
Test Voltage Nominal 9 volts
Temperature Range
Operating 40 0F to 120 0F
Storage (-15 0C to +60 0C)
Relative Humidity 0% to 90% (non-condensing)
Resolution One order of magnitude
Changeover Point 1/2 decade on a logarithmic scale(3.16x10n)
Changeover Point +/- 1/2 decade
Accuracy +/-10%
Repeatability +/-5%
Weight 6 ounce
Dimensions 130mmx70mmx25mm
Surface Resistance Checker Calibration Procedure
This product has been produced using 1% metal film resistors and high speed OP-AMP integrated circuits. The calibration procedure is based open the product being linear technology.
Its changeover points are determined on resistance and + or ?1/2 decade on logarithmic scale i.e. (3.16x10n). The linearity of the changeover points are +/- 10% from the mean value per unit.
Test equipment required
Resistance decade box
Test leads
The resistance decade box required will need a range of from > 1 kilohm up to 999 meg ohms or 10/9. Measurements greater than 10/9 are calculated using cad generated techniques, as high resistance greater than 10/9 are difficult to verify with a test voltage of 9 volts. Connect the test leads from the resistance decade box to the two test probes of the checker. Set the decade box to the desired resistance i.e. 10/3=1k, then press and hold the checker's test button, the 10/36 LED should light, 10k, 10/4 LED should light and so on. To measure the changeover point between decades, increase the resistance of the decade box while pressing the checker's test button. Record the resistance when the next LED lights permanently (this is the changeover resistance).
Example: The first green LED is illuminated 10/3=1 kilohm. At 3 or 4 kilohms 10/4 LED is illuminated the changeover point is 3 or 4 kilohms,
10/4=k
| Post Date: | 4/20/2008 |
| Expiry Date: | 10/17/2008 |
| Other Price Terms: | 200 |