Humboldt H-2783 User Manual

05.10

product manual

H-2783

METER NUMBER:

DATE TESTED:

PREDETERMINED INITIAL PRESSURE LINE:

1

Humboldt Pressure Meter— H-2783

Easy-to-use stainless clamping system employs four, one-piece,
self-locking clamps to seal lid to base with proper tension. O-ring
assures watertight seal. Easy-to-read (to nearest 1/10th %) 4-inch diam­eter direct percentage gauge with calibration adjustments.
Features all-brass H-2785.DB super pump for reliability and faster opera­tion. Unique pop-it valve eliminates seal failures. Complete
with high-impact horizontal plastic carrying case, syringe, tamping rod,
strike-off bar, calibration vessel, inside and outside calibration tubes and
instructions.

All our Type-B Concrete Air Meters feature our all-brass H-2785.DB
Super Pump for reliability and faster operation.

All air meters meet ASTM C231; AASHTO T152.

2

Operation Instructions

1. Fill the base with a sample of fresh concrete according to ASTM
C231 specifications. Next, strike off the base level full with the strike
off bar that is furnished with the instrument. Wipe top of base and
cover clean.

2. Clamp cover on securely, with petcocks open.

3. Using the supplied syringe, inject water through one petcock until
all the air is displaced and expelled through the opposite petcock.
Leave petcocks open at the time.

4. With the built-in pump, pump air to the initial pressure line on the
gauge.

5. Wait a few seconds and stabilize hand on dial at the initial pressure
by pumping up or bleeding off with the air release valve, whichever
is necessary.

6. Close both petcocks, then press down on the needle valve lever to
release the air into the base. Hold the needle valve lever down a
few seconds while lightly tapping on the gauge with your finger to
stabilize the hand on the gauge.

7. Read the percent of entrained air in the concrete on the dial.

8. After you release the pressure, clean the base, cover and petcock
openings thoroughly with running water. To check the accuracy,
refer to the calibration instructions below.

To Check Calibration of Meter Gauge

1. Fill the base full with water.

2. Screw on the short piece of straight tubing supplied with the unit
into the threaded petcock hole located on the underside of the
cover. Clamp the cover on the base with the tubing extended down
into the water.

3. With both petcocks open, add water with the syringe through the
petcock until all of the air is forced out of the opposite petcock.
Leave both petcocks open.

4. Pump up air pressure to a little beyond the pre-determined initial
pressure line on the gauge. Wait a few seconds for the compressed
air to cool to normal temperature and then stabilize the gauge hand
at the proper initial pressure line by pumping or bleeding off as
needed.

3

5. Close both petcocks and immediately press down on the thumb le-

ver exhausting air into the base. Wait a few seconds until the hand is
stabilized. If all of the air was eliminated and the initial pressure line
was correctly selected, the gauge should read zero. If two or more
tests show a consistent variation from +/- 0.1% in the result, then
change the initial pressure line to compensate for the variation. Use
the newly established initial pressure line for subsequent tests.

6. Screw the supplied curved tube into the outer end of the petcock

and by pressing on the thumb lever and controlling flow with the
petcock lever. Fill the supplied 5% calibrating vessel (354ml) level
full of water from the base.

7. Release the air at the free petcock. Open the other petcock and let

the water in the curved pipe run back into the base. There is now 5%
air in the base.

8. With both petcocks open, pump air pressure in the exact manner as

outlined in step

4. Close the petcocks and immediately press the thumb lever. Wait a

few seconds for exhaust air to warm to normal temperature and for
the needle to stabilize. The dial should now read 5%.

9. If two or more consistent tests show that the gauge reads incorrectly

at 5% air in excess of +/- 0.1% (or whatever is considered satisfac­tory), then remove the gauge glass and reset the dial hand to 5% by
turning the calibration screw located on the indicating pointer.

10. When the gauge hand reads correctly at 5%, additional water may

be withdrawn in the same manner to check results at 10%, 15%,
20%, etc.

Maintenance Tips

1. Prompt cleaning with water of the air meter cover and pot, both

inside and out will ensure a proper seal and volume are maintained.

2. Periodic oiling of petcock screws will prevent them from seizing.

WD-40 or a similar product is sufficient.

4

H-2785.12

H-2785.7

H-2785.14

H-2785.13

H-2785.15

H-2783.3

H-2783.17

H-2783.21

H-2783.2

H-2785.18B

H-2785.11

H-2785.18A

H-2785.41

H-2783.29

H-2783.5

H-2783.6

H-2783.6A

H-2785.DB

H-2783.4

H-2785.1

H-2785.21

H-2783 Replacement Parts

H-2783.4

H-2783.26

H-2783.20

H-2783.26

H-2783.29

H-2783.19

H-2783.28

H-2783.27

H-2785.1 Pressure chamber

H-2783.2 Pressure chamber cap

H-2783.3 Pressure chamber elbow

H-2785.4 Pressure chamber gasket

H-2783.5 Air-release stem

H-2783.6 Air-release cap

H-2785.7 Air meter gauge

H-2783.6A Release cap gasket

H-2785.11 Needle valve stem

H-2785.12 Needle valve nut

H-2785.13 Needle valve lever

H-2785.14 Needle valve spacer

H-2785.15 Needle valve O-ring

H-2783.17 Needle valve spring

H-2785.18A Needle valve seat assembly

H-2785.18B Needle valve seat bushing

H-2783.19 Cover

H-2783.20 Cover O-ring

H-2783.21 Needle valve spring retainer

H-2783.24 Cover Petcock

H-2785.29 Base

H-2785.41 Needle valve seat gasket

H-2785.51 Pump piston O-ring

5

H-2785.53 Pump tube O-ring

H-2783.26 Latch Assembly

H-2783.27 Latch

H-2783.28 Clamp Tap

H-2783.29 Latch Assy. screw

H-2785.DB Super Pump Assembly

H-2785.DB10

H-2785.DB12

H-2785.DB5

H-2785.53

H-2785.DB9

H-2785.DB7

H-2785.DB3

H-2785.DB2

H-2785.51

H-2785.DB6

H-2785.DB4

H-2785DB Super Pump Replacement Parts

H-2785.DB1 Valve nut

H-2785.DB2 Valve

H-2785.DB3 Valve O-ring

H-2785.DB1

H-2785.DB4 Pump tube

H-2785.DB5 Pump cap

H-2785.DB6 Stem nut

H-2785.DB7 Pump piston

H-2785.DB9 Pump stem

H-2785.DB10 Pump handle

H-2785.DB12 Stem cap

H-2785.51 Pump piston O-ring

H-2785.53 Pump tube O-ring

6

Warranty

Humboldt Mfg. Co. warrants its products to be free from defects in
material or workmanship. The exclusive remedy for this warranty is
Humboldt Mfg. Co., factory replacement of any part or parts of such
product, for the warranty of this product please refer to Humboldt
Mfg. Co. catalog on Terms and Conditions of Sale. The purchaser is
responsible for the transportation charges. Humboldt Mfg. Co. shall not
be responsible under this warranty if the goods have been improperly
maintained, installed, operated or the goods have been altered or
modified so as to adversely affect the operation, use performance or
durability or so as to change their intended use. The Humboldt Mfg.
Co. liability under the warranty contained in this clause is limited to the
repair or replacement of defective goods and making good, defective
workmanship.

Humboldt Mfg. Co.

875 Tollgate Road
Elgin, Illinois 60123 U.S.A.

Testing Equipment for

HUMBOLDT

www.humboldtmfg.com

U.S.A. Toll Free: 1.800.544.7220

Voice: 1.708.456.6300

Fax: [phone]

Email: [e-mail]

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