Varec 2500, Installation And Operation Manual

Page: 51 / 124

Varec, Inc. 41
4. Check that the float is at zero level with the tape taut.
5. If calibration is required, proceed to the next section.
6. Tighten the dial plate screws
(40)
, being careful to not overtighten them.
Calibrate the Counter
Note These instructions apply to systems that use a hollow-shell, welded float that is
14.5 inches (368 mm) in diameter by 4.0 inches (102 mm) deep. Calibration is based upon
the standard specific gravity of water (1.0). The value set on the dial plate
(7)
is the water-
line level on the float as it contacts the bottom of the tank. Refer to the table below to
determine the setting for the dial plate.
Caution Be careful not to pull up and disengage or drop the pinion gear
(24)
. If the pinion
gear is disengaged, it may be necessary to disassemble and reassemble the counter mech-
anism to properly calibrate the gauge. Refer to Chapter , if this becomes necessary
Note If the dial and counter drums have not been reset to zero as described in the pre-
ceding section, perform those steps first.
Note The counter must be re-calibrated after product is placed in the tank.
1. Determine the value at which to set the dial.You can determine the value from the table
below or from specific gravity tables for the product that will be (or is) in the tank. Alter-
natively, use a hand gauge to determine product level.
2. Rotate the dial to the determined value.
Note If it is necessary to disassemble the counter mechanism, refer to Figure 10 on
page 66, or for more instruction detail, refer to section , "Counter Wheel Assembly" on
page 66.
3. Tighten the dial plate screws
(40)
, being careful not to overtighten them.
Table 4: Initial Calibration Table
Caution Do not attempt to hand crank the float above (through) a floating roof. Hand-
cranking the tape beyond this point on a floating roof installation can damage and snap
the tape!
4. Observe the operation of the counter drums and dial, while slowly cranking the float to
the top of the tank and then lowering it to the bottom. The counter drums and dial should
rotate freely and return to the calibrated indication when the float touches the tank bot-
tom.
Gauge Head Units x Minimum
Increment Counter Drum Settings Dial Setting
(s.g. = 1.0)
Corresponding
Measure
ft. & in. x 1/16 in. - 0 0 2 2 inches
ft. & 1/10 ft. x 1/100 ft. - 0 0 16.5 0.165 ft.
meters x 1/1000 M 0 0 0 51 4 inches