TB-6550 December 2010 Page 1 of 4
Full Time Continuous Monitor
Operation, Installation and Maintenance
Figure 1. EMIT Full Time Continuous Monitor
Description
Leading companies use continuous monitors as a cost
effective component in satisfying the paragraph 6.1.3
Compliance Verification Plan requirements of ANSI/
ESD S20.20. The EMIT Full Time Continuous Monitor
provides 100% monitoring of both the operator and the work
surface. This unit provides continuous monitoring of:
• One user wearing a wrist strap
• ESD worksurface
• Ground (50514 only)
Note: Worksurface must have a conductive layer such as
Dual Layer Rubber, Dissipative 3-Layer Vinyl or Micastat®
Dissipative Laminate with conductive buried layers. EMIT
Continuous Monitors are not recommended for use with
homogeneous matting.
If the unit detects that the elements are outside industry
standards, the continuous monitor will alarm by both an
audible signal and an illuminated red LED to notify the user of
a problem.
Unlike many units, the Full Time Continuous Monitor
(50514 only) also continuously verifies ground (AC outlet
ground). When the Power Cord is plugged in, a self-test runs
automatically. If the AC outlet is wired incorrectly, both red
LEDs will illuminate and the audible alarm will sound. The
unit has an additional wrist strap ground point banana jack for
a second user or supervisor.
The Full Time Continuous Monitor is available in two
models:
Model Description
50514 Full Time Cont. Monitor
50519 Full Time Cont. Monitor
EMIT - 3651 Walnut Avenue, Chino, CA 91710 • (909) 664-9980 • Fax (909) 627-7449 • Website: DescoEMIT.com
TECHNICAL BULLETIN TB-6550
120 VAC
220 VAC
Voltage
ADVANTAGES OF WORKSTATION CONTINOUS
MONITORING OVER PERIODIC TESTING
Many customers are eliminating periodic testing and are
utilizing workstation continuous monitoring to better ensure
that their products were manufactured in an ESD controlled
environment. Full time workstation continuous monitoring
is superior to pulsed monitoring as well as periodic testing,
and can save a significant amount of money in testing costs
and rejected products. Periodic testing detects failures after
ESD susceptible products have been manufactured. The
costs of dealing with the resulting catastrophic or latent
defects can be considerable. Full Time Continuous
Monitors eliminate the need for users to test wrist straps
and log the results; by their function, these monitors satisfy
the ISO 9000 and ANSI/ESD S20.20 Paragraph 6.2.2.2.
test logging requirements. Per ESD-S1.1 paragraph 6.1.3
Frequency of Functional Testing “Daily (Wrist Strap) testing
may be omitted if constant monitoring is used.”
Per ESD Handbook TR 20.20 paragraph 5.3.2.4.4 Test
Frequency “Because wrist straps have a finite life, it is
important to develop a test frequency that will guarantee
integrity of the system. 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.”
WAVE DISTORTION DETECTION TECHNOLOGY
PROVIDES TRUE 100% CONTINUOUS MONITORING
EMIT utilizes wave distortion technology for the Full Time
Continuous Monitor, which is an Impedance type monitor.
Per ESD TR12-01 section 2.2 Impedance (or single wire)
constant monitors “The capacitance type of monitor is
also known as an impedance monitor. They both work on
the same theory, however the impedance monitor uses
a detection circuit designed to reduce false alarms and
eliminate adjustments. ‘Single Wire’ or ‘impedance type’
monitors use the phase difference between current and
voltage to detect changes in impedance of the cord, band
and person. A very low AC voltage is used for constant
sensing. Any standard wristband and coiled cord can be
used.”
Thus the wave distortion circuitry monitors current/voltage
phase shifts and provides true 100% continuous monitoring.
Electrical current will lead voltage at various points due to
the combinations of resistance and capacitive reactance.
By monitoring these “distortions” or phase shifts, the
wave distortion Full Time Continuous Monitor will reliably
determine if the circuit is complete.
© 2009 DESCO INDUSTRIES INC.
Made in America
Employee Owned
