19212 Desco, 19212 Datasheet - Page 2

• Manufacturer Part Number: 19212
• Description: MONITOR WORKSTATION MINI 120V
• Manufacturer: Desco
• Type: Monitorr

Specifications of 19212

• Features: 10mm Studs and Sockets
• Power Supply Type: 120V AC
• Color: Sapphire
• Size: 2.77 in x 2.07 in
• Operation: Continuous
• Size, Stud: 10 mm
• Voltage, Operating: 120 V
• For Use With/related Products: Wrist Strap & Table Mat
• Lead Free Status / RoHS Status: Not applicable / Not applicable
• For Use With: Desco mat types T2, Z2, O, and CE
• Other names: 16-1083

TB-3004 Page 2 of 4
Wave Distortion Detection Technology
Provides True 100% Continuous
Monitoring
Wave distortion impedance 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 Jewel
Continuous Mini Monitor will reliably determine if the
circuit is complete.
Wave distortion technology can be referred to as “vector
impedance monitoring”. This description is valid as the
wave distortion technology measures the impedance
at the monitored banana jack and looks for changes in
either the capacitance or resistance of the circuit which
includes the wrist strap and its wearer. It uses
filtering and time domain sampling to filter out false
signals caused by voltage offsets, 60 Hz fields and
other electro-magnetic and electrostatic interference.
In normal factory environments, and with persons
whose capacitance with respect to ground is within
design limits (5 feet tall 90 pound person to 6 foot 5 inch
250 pound person), the Jewel
Continuous Mini Monitor cannot be “fooled”. It will
provide a reliable alarm only when the wrist strap or
work surface becomes dysfunctional or unsafe
according to accepted industry standards. The Jewel
Workstation Continuous Mini Monitor is drift-free and
designed to be insensitive to the effects of squeezing or
stretching the coil cord.
Advantages Of Wave Distortion And
Single-Wire Technology
The Jewel
allows the use of any standard, single-wire wrist strap
and coil cord. The monitor/wrist strap/cord system
life-cycle costs are by far lower than alternative systems
which require expensive and less durable dual-wire
cords and special wrist straps. The Jewel
Workstation Continuous Mini Monitor is an
economical way to monitor both the operator’s wrist
strap and workstation surface. See “Maintenance and
Calibration” (page 4) to minimize life-cycle costs.
The dictionary defines constant as uniform and
unchanging, and continuous as uninterrupted.
Nonetheless, some dual-wire resistance monitors utilize
a pulsed test current and do not provide continuous
monitoring. For example, during each 2.2 second pulse
cycle of a leading “constant” resistive monitor, electrical
current is pulsed for only 0.2 seconds followed by an
unmonitored interval of 2 seconds. This leaves the user/
®
Workstation Continuous Mini Monitor
DESCO EAST - One Colgate Way, Canton, MA 02021-1407 • [phone] • Fax [phone] • Web Site:
DESCO WEST - 3651 Walnut Avenue, Chino, CA 91710 • [phone] • Fax [phone]
®
Workstation
®
Workstation
®
®
wrist strap unmonitored for over 90% of each cycle.
Damaging static charges can easily occur in the
portion of the time in between the pulses. The off period
of 2 seconds equals 2 billion nanoseconds, and “it takes
only about 25 volts applied for 100 nanoseconds to blow
most memories or microprocessors”.*
By using the reliable wave distortion impedance
technology to determine if the circuit is complete, there
are no false alarms. There is no need to adjust or tune
the monitor to a specific user or installation. The
miniscule amount of electrical current (less than 1 volt
coil cord signal) required to generate the waveform has
never caused reported skin irritation and is extremely
safe for use in voltage sensitive applications such as
disk drive manufacturing.
Worksurface Channel
The Jewel
monitoring circuitry is sufficiently sensitive to detect
extremely low current, allowing it to be used with mats
having a resistance of up to 5 x 10E8 ohms RTG.
When the Monitor is connected to an ESD Mat
worksurface, the amount of current that flows is a
function of the total resistance between the monitor and
through the worksurface to ground. When the resistance
of the worksurface is below a pre-set threshold, the
monitor will indicate good. Conversely, if the resistance
level is high when compared to the monitor’s reference,
the unit will alarm. This is an integrating resistance
measuring circuit, therefore it is relatively insensitive to
externally induced electromagnetic fields. The
resistance threshold is factory set to 500 megohms.
(It can be special ordered to other limits. Limits can be
varied and set to 1 gigohm maximum.)
Installation
Confirm that the surface resistance (RTG) of the mat is
5 x 10E8 ohms or less and has a conductive layer. We
recommend the Desco 19780 or 19635 Tester. Remove
the monitor from its packaging and inspect for any
shipping damage. Included with each Jewel
tion Continuous Mini Monitor should be:
1 120 VAC Adapter
2 Push and clinch snaps (09863)
The Continuous Mini Monitor is normally installed
toward the front edge of a workstation where the LEDs
are easily visible. The unit is designed to be snapped on
the worksurface using the 10mm snap studs mounted at
the bottom of the monitor. See figure 2.
*1981 article by Donald E. Frank - Electrical Overstress /
Electronic Discharge Symposium Proceedings
®
Workstation Continuous Mini Monitor
Desco.com
© 2011 DESCO INDUSTRIES INC.
®
Worksta-
Employee Owned