TB-3014 Page 6 of 7
2010 DESCO INDUSTRIES INC.
Employee Owned
DESCO WEST - 3651 Walnut Avenue, Chino, CA 91710 (909) 627-8178
DESCO EAST - One Colgate Way, Canton, MA 02021-1407 (781) 821-8370 Website:
Desco.com Testing / Verification (cont.)
EQUIPMENT:
Digital Multimeter - accurate to 1.25% @ 10VDC and 100VDC
Fixed Decade Box value 10E3 - 10E12 - accurate to ±2.5%,
except at 10E11 and 10E12 (±5%)
Thermometer - accurate to ±1°F
Humidity meter - accurate to 2%
Test leads
99% Isopropyl alcohol and cleaning wipes
SET UP:
A .Test Area - Area needs to be free of any high voltage
transformer or power supply. Not under any type of fluorescent
lighting or high power lighting.
B. Worksurface - needs to be covered with conductive mat at 1.0
x 10E3 or less, connected to equipment ground.
C. Technician - needs to be grounded with zero ohms resistor to
equipment ground.
D. Decade Box - needs to be grounded to earth ground.
*Accuracy is measured after normalizing the instrument at
70-80 °F and 30-50% RH for a minimum of 4 hours.
NORMALIZATION OF METER
Temperature inside testing area needs to be 75°F @ ±6.6% 40%
to 60% RH. Meters need to stay at constant temperature 75°F
@ ±6.6% for about 2 hours for proper reading. Meters cannot
be inside objects, enclosed boxes, containers or cases unit is
supplied with (temperature inside case will differ from outside
temperature, cases will act like an insulator to the Meters), Meters
will have to be stationary in testing area for about 2 hours with no
significant temperature changes.
TESTING OF SURFACE RESISTANCE METER
When testing use only the leads supplied with the Meter. DO
NOT TEST WITH RESISITIVITY ATTACHMENT, Resitivity
Attachment will give a much higher reading and is only
designed for periodic checks.
With 10V/AUTO switch down, press Test Button - voltage
between the two leads should be 10V ±5%
With 10V/AUTO switch up, press Test Button - voltage between
the two leads should be 100V ±5%
Using the cleaning wipes and 99% isopropyl, clean around
banana jack and mono jack where leads connects to, oil from
human fingers can alter accuracy.
Make sure 10V/AUTO switch is set to AUTO (switch up).
Testing each decade starting from 1.0 x 10E12 and down,
never start from 1.0 x 10E3.
Temperature
Fahrenheit
= 75°F ±6.6%
Celsius
= 23.8°C ±10.2%
Relativity Humidity ±10 Digits
A. 1.0 x 10E12
+ 20%
LED = 12 Yellow Mantissa 1.20
0%
LED = 12 Yellow Mantissa 1.00
- 20%
LED = 11 Yellow Mantissa 8.00
B. 1.0 x 10E11
+20%
LED = 11 Yellow Mantissa 1.20
0%
LED = 11 Yellow Mantissa 1.00
-20%
LED = 10 Green Mantissa 8.00
C. 1.0 x 10E10
+10%
LED = 10 Green Mantissa 1.10
0%
LED = 10 Green Mantissa 1.00
-10%
LED = 9 Green Mantissa 9.00
D. 1.0 x 10E9
+10%
LED = 9 Green Mantissa 1.10
0%
LED = 9 Green Mantissa 1.00
-10%
LED = 8 Blue
Mantissa 9.00
E. 1.0 x 10E8
+10%
LED = 8 Blue
Mantissa 1.10
0%
LED = 8 Blue
Mantissa 1.00
-10%
LED = 7 Blue
Mantissa 9.00
F. 1.0 x 10E7
+10%
LED = 7 Blue
Mantissa 1.10
0%
LED = 7 Blue
Mantissa 1.00
-10%
LED = 6 Blue
Mantissa 9.00
G. 1.0 x 10E6
+10%
LED = 6 Blue
Mantissa 1.10
0%
LED = 6 Blue
Mantissa 1.00
-10%
LED = 5 Green Mantissa 9.00
H. 1.0 x 10E5
+10%
LED = 5 Green Mantissa 1.10
0%
LED = 5 Green Mantissa 1.00
-10%
LED = 4 Green Mantissa 9.00
I. 1.0 x 10E4
+10%
LED = 4 Green Mantissa 1.10
0%
LED = 4 Green Mantissa 1.00
-10%
LED = 3 Red
Mantissa 9.00
J. 1.0 x 10E3
+10%
LED = 3 Red
Mantissa 1.10
0%
LED = 3 Red
Mantissa 1.00
-10%
LED = <3 Red
Mantissa <0.90