Desco 19330 Installation, Operation And Maintenance Manual

Full-Time Continuous Monitor
Installation, Operation and Maintenance
Figure 1. Desco Full-Time Continuous Monitor
Description
The Desco Full-Time Continuous Monitor is a single
workstation continuous monitor. It continuously monitors
the wiring of an AC outlet, path-to-ground integrity
of one operator, and the ground plane of one ESD
worksurface. Mounting tabs make it suitable to install in
workbench or equipment settings. The embedded relay
terminal activates when a pass condition is displayed
on the monitor and can be connected to machines for
access control or other devices. Connect the 19332
Light Tower accessory for increased alarm visibility.
Connect the 19333 Power Relay accessory to control
power to workbenches, hand tools, and other electronic
devices dependent on the Full-Time Continuous
Monitor's status.
The Full-Time Continuous Monitor is designed
with Wave Distortion Technology to provide stable
continuous monitoring of the path-to-ground and
presence of 1 megohm resistance of an operator's wrist
strap. Audio and visual alarms activate (in less than
500 milliseconds) when the operator unintentionally
disconnects from the monitor or the wrist strap
connection points are intermittent. The Full-Time
Continuous Monitor also monitors for a worksurface
path-to-ground of less than 10 megohms and the
integrity of the electrical ground used to by the monitor.
All Full-Time Continuous Monitors are calibrated to NIST
standards.
TB-3092 Page 1 of 7 February 2023
Test Equipment Depot - 800.517.8431 - TestEquipmentDepot.com
TECHNICAL BULLETIN TB-3092
Wave Distortion Technology is the Most Reliable
Technology for the Continuous Monitoring of
Single-Wire (Conductor) Wrist Straps
"Wave Distortion" or vector impedance works by
applying a continuous test voltage of 1.2 volts
peak-to-peak at 1 to 2 microamperes (0.000002
amperes) to the wrist strap that is connected to the
continuous or constant monitor. The test voltage creates
a square wave that the monitor circuit compares to
established patterns. By monitoring the "distortions", or
shape of the square wave, Wave Distortion Technology
determines if the monitored circuit is complete - the
operator is in the circuit and the total equivalent DC
resistance is within specifications. Wave Distortion
Technology produces a very fast alarm time and
minimal false alarms.
ANSI/ESD S20.20 section 7.3 states "Compliance
verification records shall be established and maintained
to provide evidence of conformity to the technical
requirements." Per ANSI/ESD S1.1 Annex A.3 Daily
(wrist strap system) testing may be omitted if constant
monitoring used." Per ESD Handbook ESD TR 20.20
section 5.3.2.4.4 "Typical Test programs recommend
that wrist straps that are used daily should be tested
daily. However, if the products that are being produced
are of such value that knowledge of a continuous,
reliable ground is needed, and then continuous
monitoring should be considered or even required."
The Full-Time Continuous Monitor and its accessories
are available as the following item numbers:
Item Description
19330 Full-Time Continuous Monitor, with North
America Power Cord
19331 Full-Time Continuous Monitor, with UK Power
Cord
19332 Light Tower
19333 Power Relay, North America
19334 Replacement Power Relay Interface Cord
19327 Replacement Power Cord, North America
19328 Replacement Power Cord, UK
98221 Wave Distortion Monitor Verification Tester
09842 Multi-Ground Hub
Made in the
United States of America
© 2023 DESCO INDUSTRIES INC
Employee Owned