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DESCO EMIT WEST - 3651 WalnutAvenue, Chino, CA 91710 • (909) 627-8178 • Fax (909) 627-7449
DESCO EMIT EAST - 90 Hudson Road, Canton, MA 02021-1407 • (781) 821-8370 • Fax (781) 575-0172 • Web Site: DescoEMIT.com
on the charger. Momentarily touch the positive terminal to the
adapter plate. The 50551reads approximately +1.10kV. By
using a stop watch or other timing device, determine the time
needed for the voltages to decrease from +1.10kV to +.01kV.
This is the positive discharge time.
7. NEGATIVE DISCHARGE MEASUREMENTS - For negative
discharge measurements, touch the (+) output terminal while
pressing the charging button on the charger. Momentarily touch
the negative terminal to the adapter plate. Follow the
instructions for the positive discharge measurement above.
IMPORTANT: A ground path must be provided between one of
the output terminals of the charging unit and the ground
reference of the Fieldmeter and Adapter Plate. This is normally
provided by holding the Charger in one hand and the
Fieldmeter with Adapter Plate in the other. If this is not
possible, you must use a test lead to connect one to the
charger output terminals and the fieldmeter ground connection.
Figure 6. Taking decay measurements.
Calibration
The overall accuracy of the 50552 Test Kit and the 50551
digital fieldmeter is +/- 5% nominal. Calibration of the meter
and the Ionization Test Kit should only be performed by the
factory. Both the 50552 and the 50551 are calibrated to NIST
traceable standards. Contact our Customer Service
Department for details.
Maintenance
BATTERY CARE
The battery in the Model 50552 and 50551 should be replaced
annually and whenever you plan an extended period of
unattended monitoring. See specifications for battery
replacement type.
CLEANING
It is important to keep the insulators on the adapter plate clean
and free of contaminates that may cause surface leakage. To
test the performance of the adapter plate, charge the plate and
note the discharge rate in a non-ionized area. The self
discharge rate to 10% of original voltage should not be less
than five minutes.
The area around the aperture of the Model 50551 must be
kept clean to ensure accurate, drift-free readings. Never touch
the aperture with anything. To remove dust or other particulate
matter, use low-pressure instrument-grade air. To remove more
severe contamination, spray or flush with the smallest practical
amount of clean technical-grade of isopropyl alcohol. Then
allow the instrument to air dry for several hours.
Specifications
Isolated Plate Assembly
Plate Capacitance: 13 picofards ± 2 picofards
Range: 0 to ± 2kV, higher voltages may
be measured
Grounding: Connection through conductive
case of Model 50551
Field meter
Weight: 1.5 oz.
Charging Unit
Output: 1100VDC monimal, <1:A Max.
Output Terminals: Two acorn buttons labeled for
"+" and "-"
Load Regulation: Better than 8% NL to FL where
FL = 109ohms
Battery Type: 9 volt alkaline
Battery Life: 40 hours
Temperature Range: +10° to +30°C (+50° to +86°F)
Relative Humidity: 10% to 80% non-condensing
Dimensions: 3.75"L x 2.88"W x 1"D
(9.53 x 7.32 x 2.54cm)
Weight: 2.8 oz. (79 gm)
Limited Warranty
Desco EMIT expressly warrants that for a period of five (5) years from the date of
purchase, Desco EMIT Ionization Test Kits will be free of defects in material (parts)
and workmanship (labor). Within the warranty period, a credit for purchase of
replacement Desco EMIT products, or, at Desco EMIT's option, the product will be
repaired or replaced free of charge. If product credit is issued, the amount will be
calculated by multiplying the unused portion of the expected five year life times the
original unit purchase price. Call our Customer Service Department at 909-627-
8178 (Chino, CA) or 781-821-8370 (Canton, MA) for a Return Material
Authorization (RMA) and proper shipping instructions and address. Please include
a copy of your original packing slip, invoice, or other proof of date of purchase. Any
unit under warranty should be shipped prepaid to the Desco EMIT factory.
Warranty replacements will take approximately two weeks.
If your unit is out of warranty, call our Customer Service Department at 909-627-
8178 (Chino, CA) or 01892 665313 (Crowborough, U.K.) for a Return Material
Authorization (RMA) and proper shipping instructions and address. Desco EMIT
will quote repair charges necessary to bring your unit up to factory standards.
Warranty Exclusions
THE FOREGOING EXPRESS WARRANTY IS MADE IN LIEU OF ALL OTHER
PRODUCT WARRANTIES, EXPRESSED AND IMPLIED, INCLUDING
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE WHICH
ARE SPECIFICALLY DISCLAIMED. The express warranty will not apply to defects
or damage due to accidents, neglect, misuse, alterations, operator error, or failure
to properly maintain, clean or repair products.
Limit of Liability
In no event will Desco EMIT or any seller be responsible or liable for any injury,
loss or damage, direct or consequential, arising out of the use of or the inability to
use the product. Before using, users shall determine the suitability of the product
for their intended use, and users assume all risk and liability whatsoever in
connection therewith.
© 2006 DESCO INDUSTRIES INC.
Employee Owned
