TB-6502
Page 6 of 8
Revision May 2007
© 2007 DESCO INDUSTRIES INC.
Employee Owned
plugged into the phono jack on the front side of the tester. (See Figure 3.) The 50407/50413
automatically determines what type of wrist strap is being tested.
The LED(s) will turn off while the test is in progress; the test results for each foot and wrist
strap will then be displayed for approximately three (3) seconds. If all test results are “SAFE”
the internal relay will be activated while the test results are displayed. The relay can be used
for opening an electric lock to an ESD sensitive area. The maximum contact rating is:
1A@30VDC.
If any of the test results are failed “HIGH” or “LOW” an audible alarm will sound. The LED(s)
indicating the failed test will be displayed for approximately three (3) seconds, and the
internal relay will not activate.
CALIBRATION AND PERIODIC TESTING:
The accuracy of the 50407/50413
is specified as:
1. +5% for 1 Megohms and lower resistance ranges.
2. +10% for 1 Megohms and higher resistance ranges.
A periodic check (once every 6 to 12 months) using a precision resistance box should be
performed to verify proper operation.
A limit comparator, the 50401, can be purchased for the convenient periodic testing of the
50407/50413.
The 50401 contains 14 standard resistors to check the following high and low limit ranges:
1. 10K low
2. 10K safe
3. 100K low
4. 100K safe
5. 1M low
6. 1M safe
7. 10M safe
8. 10M high
9. 35M safe
10. 35M high
11. 100M safe
12. 100M high
13. 1G safe
14. 1G high
TESTING PROCEDURE:
Wrist strap operation test.
1. Insert the 50401/50407/50413 test plug into the dual wrist strap connector on the
50407/50413.
