TB-3004 March 2011 Page 1 of 4
Figure 1. Jewel
Description
The Jewel
independently monitors the operator and the
worksurface. The instant an operator’s wrist strap or
cord fails, the monitor will issue audible and visual
alarms alerting the user of the problem. In the same
manner, the unit also confirms that a path to ground of
less than 500 megohms exists from the ESD
worksurface.
The Jewel
Conductor Impedance Sensing Continuous Monitor
which per ESD Handbook TR20.20 section 5.3.9.2.1 “a
small AC voltage is used in a detection circuit designed
to eliminate false alarms and adjustment. They use the
phase difference between current and voltage to detect
changes in impedance of the grounding cord, wristband
and person. No adjustments are required.”
Per ESD Handbook ESD TR20.20 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 monioring should be considered or
even required.”
The Jewel
available in the following model.
Workstation Continuous Mini Monitor
Operation, Installation, and Maintenance
Model
19212
®
®
®
Workstation Continuous Mini Monitor
Workstation Continuous Monitor is a Single
Workstation Continuous Mini Monitor is
Sapphire
Color
DESCO EAST - One Colgate Way, Canton, MA 02021-1407 • (781) 821-8370 • Fax (781) 575-0172 • Web Site:
®
Workstation Continuous Mini Monitor.
TECHNICAL BULLETIN TB-3004
DESCO WEST - 3651 Walnut Avenue, Chino, CA 91710 • (909) 627-8178 • Fax (909) 627-7449
Input/Output
Voltage AC
120/24
Calibration
NIST
Advantages Of Continuous Monitoring
Over Periodic Testing:
“When considering constant [or continuous] monitors,
the equipment cost including the wrist strap,
maintenance and training cost, labor time for performing
wrist strap tests, and the potential failures due to
non-functional wrist straps should be considered.
A broken wrist strap may expose products to ESD over
an entire shift if it is checked only at shift change with
wrist strap checker.” (ESD TR 12-01 Section 4.2
Selection Considerations)
The Jewel
the need for periodic wrist strap tests and logging.
Continuous monitoring is superior to periodic or pulsed
testing, and can save a significant amount of money
in testing costs and rejected product. Periodic testing
detects failures after ESD susceptible products way
have been manufactured. The costs of dealing with the
resulting catastrophic or latent defects can be
considerable. Jewel
Monitors eliminate the need for operaters to test wrist
straps and log the results; by their function, these
monitors satisfy the ISO 9000 and ANSI/ESD S20.20
test logging. ANSI/ESD S20.20 Section 6.2.2.2
Personnel Grounding Guidance states “A log should be
maintained which verifies that personnel have tested
their personal grounding devices.” Per ANSI/ESD-
S1.1 Annex A Section 6.1.3 “Daily (wrist strap system)
testing may be omitted if constant monitoring is used.”
Per ANSI/ESD-S1.1 Annex A Frequency of Functional
Testing, “The wrist strap system should be tested daily
to ensure proper electrical value. Daily testing may be
omitted if constant monitoring is used.”
Park Snap
The audible alarm is designed to alert both operator and
supervisor. The Park Snap feature provides a means
for an operator to disconnect when normally leaving
the work area, without the audible alarm sounding, and
wrist cord storage (visual red LED will illuminate). When
the operator touches the Park Snap, the audible alarm
is disabled for about 8-10 seconds. The operator can
remove the wrist strap cord and attach socket of the
cord to Park Snap for storage. The operator can
separate the coil cord from the wrist band and attach
the coil cord snap to the park snap for convenient
storage. The coil cord may also be removed from the
jack on the Jewel
Once the coil cord is in the park position, the
operator ground status light will remain red.
®
Workstation Continuous Monitor eliminates
®
monitor without the alarm sounding.
®
Workstation Continuous Mini
Desco.com
© 2011 DESCO INDUSTRIES INC.
Made in America
Employee Owned
