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31 Cards in this Set
- Front
- Back
Alnor EBT720/721 and ProHood PH720/721
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It's an electronic micromanometer
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Alnor EBT720/721 and ProHood PH720/721 Features: |
conversions between actual and standard flow Discrete or continuous display and data logging |
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Pitot tube used for what?
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2. air volume 3. velocity pressure WITHIN DUCTWORK |
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Static Pressure Probe |
Primarily to obtain static pressure measurements within ductwork. |
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Velocity Matrix= Velgrid
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Installing Batteries |
Know there is a battery selector switch for type of battery |
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Connecting a pitot tube |
static pressure port is connected to negative pressure port on micromanometer (-), and total pressure port connected to +. |
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Connecting Static Pressure Port
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Static pressure port connected to + port. Negative remains open to atmosphere. |
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Attaching to Capture Hood |
2. Attach temp cable and back pressure flap swich cable to right side of meter. |
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Matrix standoffs positioned where?
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Positive side of matrix. |
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Connecting the Airflow Probe |
+ to +, - to - |
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READ |
if set to RUNAVG, then pressing READ alternates pause/resume. Red button on hood has same function as READ key. |
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Logging Interval
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When logging set to CONTIN, then meter will log readings at the frequency. |
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If you select flow for a pitot tube or air flow probe
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you will need to enter duct shape and size. |
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Entering K-factor
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Range from 0.5 to 1.5 |
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K-factor mandatory for what? |
Range 0.001 to 9.999 |
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View/Set Standard Pressure and Temperature |
If not plugged in, then you enter them! |
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When is temp/pressure not used?
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For the Diffuser Flow tool (Flow from Pressure and K-factor) |
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Discrete vs Continuous Logging |
Continuous= automatically saves at selected logging interval |
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Taking Back Pressure Compensated Hood Readings |
2. Hold hood to diffuser 3. Press READ or red switch 4. Close flap when "CLOSE THE FLAP" is displayed 5. Close flap and press READ |
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Deadband |
Sets min where zero is displayed. If on, then less than 18 fpm or 18cfm display zero. |
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Calibrate |
Possible fro pressure, temp and humidity in field. Need to expose to as close as requested calibration condition. |
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Calibration Notes: |
Calibration for temp robe and hood base temp sensor are stored in micromanometer, and cal will not follow the probe to a different micromanometer. |
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Non back pressure compensated measurements: Where is flap?
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Open |
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"888888" |
pressure to high to measure (or velocity) |
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Set of error codes- look at manual if needed! |
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Verifying Flow Measurements |
Recommended with multi-point, in duct velocity traverses using a Pitot-static tube or a thermal anemometer. |
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DP Absolute Pressure Velocity Volume Temp RH |
DP= +-15 in H20 Absolute Pressure= 15 to 40 in Hg Velocity= 25 to 8,000 ft/min PITOT, 25 to 5k ai flow probe, 25 to 2,500 matrix Volume= 25 to 2,500 cfm on capture hood Temp= -40 to 250 RH= -4 to 160 |
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Resolution: Pressure Velocity Volume Rh Temp |
Pressure= 0.00001 in H20 Velocity= 1 ft/min Volume= 1 cfm Rh= 0.1% Temp= 0.1F or 0.1C |
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Accuracy: Pressure Velocity Volume Rh Temp |
Pressure: +- 2% +- 0.001 in H20 Velocity +-3% or +-7 ft/min Volume +-3% +-7cfm Rh +-3% Temp mostly +-5% but sliding scale |
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Response Time
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2 to 8 seconds |