ADM-850L 07/29/092
2.0 SPECIFICATIONS
AIR VELOCITY: Measured in feet per minute (fpm), or meters per second (m/s), corrected for local air density. The
measurement range is 25 to 29,000 fpm with a Dwyer Series 160 standard pitot tube. Accuracy is ± 3% of reading
± 7 fpm from 50 to 8000 fpm. Pitot tube velocity readings from 8,000 fpm to 29,000 fpm are based on compressible
isentropic flow theory and are not certified NIST traceable.
NOTE: The ADM-850L AirData Multimeter is NOT designed to be used with the AirFoil probe or the VelGrid. Velocity
readings taken using an ADM-850L AirData Multimeter and an AirFoil probe or a VelGrid will NOT be correct.
DIFFERENTIAL PRESSURE: Measured in inches of water column (in wc) or Pascals (Pa). The measurement range is
from 0.0001 to 60.00 in wc. Maximum safe pressures are 20 psid (900% full scale) and 60 psia common mode.
Accuracy is ± 2% of reading ± 0.001 in wc from 0.0500 to 50.00 in wc.
ABSOLUTE PRESSURE: Measured in inches of mercury (in Hg) or bars with reference to a vacuum. The measurement
range is 10-40 in Hg. Maximum safe pressure is 60 psia. Accuracy is ± 2% of reading ± 0.1 in Hg from 14 to 40 in
Hg.
TEMPERATURE: Accuracy is ± 0.5/F from 32/F to 158/F with a resolution of 0.1/F using the ADT442, ADT443, ADT444,
ADT445 or ADT446 TemProbes. Meter displays readings from -67.0/F to 250.0/F. Safe exposure range for the
TemProbe is -100/F to 250/F. Do not expose the plastic base of the TemProbe or extension wand to temperatures
above 200/F.
AIR FLOW: Measured in cubic feet per minute (cfm) or liters per second (L/s), corrected for local air density. This function
requires the use of the Shortridge Instruments' Series 8400 Backpressure Compensating FlowHood System. The
measurement range is 25 to 2500 cfm supply and 25 to 1500 cfm exhaust. Accuracy is ± 3% of reading ± 7 cfm from
100 to 2000 cfm (nonbackpressure compensated readings).
NOTE: The FlowHood may require the development and use of correction factors when used on swirl diffusers, or
on other types of diffusers with uneven air throw. The FlowHood may not be appropriate for use on small supply
outlets at high jet velocities or “nozzle” type outlets. These outlets cause an extreme concentration of air velocity
on portions of the flow sensing grid. The FlowHood readings may be inaccurate under such conditions.
Consideration must be given to other system components, such as may be encountered on some single supply air
outlet applications, where the FlowHood's slight backpressure may directly affect fan performance.
AIR DENSITY CORRECTION: The air density correction range is 14-40 in Hg and 32/F to 158/F for correction of air flow
and velocity measurements. The readings represent local density air flow or velocity corrected for the density effects
of temperature and absolute pressure.
RESPONSE TIME: Varies from one second at higher pressure inputs to seven seconds at less than 0.0003 in wc (70 fpm).
Extremely low pressure/flow/velocity inputs require longer sample times than higher pressure/flow/velocity inputs.
TREND mode provides continuous readings in less than two second intervals. (Accuracy specifications do not apply
in TREND mode).
READOUT: Ten digit, 0.4 inch, liquid crystal display (LCD).
METER HOUSING: High impact, molded, "T" grade ABS.
METER WEIGHT: 36 ounces (1.02 kg), including batteries.
SIZE: 6.0" x 6.4" x 2.7" (15.2 x 16.3 x 6.9 cm).
BATTERY LIFE: A ten-hour charge will normally allow two working days of heavy use, or up to 3000 readings per charge
if the back-light is not being used. Increasing the charge time to 48 hours (such as a weekend) will increase the
working time by 25%. Continuous use of the back-light may reduce the battery life by up to one half.
A set of rechargeable type AA NiCad batteries is supplied in each meter. Each battery has a storage capacity of
1100 milliAmp hours. These batteries may be recharged up to 500 times before replacement. If 1100 mAh batteries
are not available in a field situation, 700 mAh batteries (all 12 ) may be substituted. If 700 mAh batteries are mixed
with 1100 mAh batteries, the 700 mAh batteries may be damaged as the battery charge is depleted. If rechargeable
batteries are not available in a field situation, the batteries may be replaced with 12 non-rechargeable "AA" pen cell
batteries.
WARNING: Do not plug the charger in if any non-rechargeable batteries are in the meter. The meter will be
seriously damaged along with the batteries and charger.
