Meriam M2110L SMART LEVEL GAUGE - Manual (Page 16)

9R143 Dated 3/2011
14
P4 – FULL TANK HYDROSTATIC PRESSURE
This register is used by the gauge to draw a relationship between measured static pressure and actual level in volume
or mass units. This register must be set to the pressure created by a FULL COLUMN of vertical fluid in the tank, in
inches of water column at 20ºC reference temperature.
To calculate this value, multiply the specific gravity 1 of the fluid (relative to water at 60
°F) by the full distance from
the floor 2 of the tank to the top of the maximum level to be measured. Then, using the appropriate scale factor,
convert the resultant pressure value to inches of water column at 20ºC reference (for example, to convert PSI to
InH
2
O @ 20ºC, multiply by 27.72978).
Note that the P4 value is not affected by installation type (bubbler system or direct head measurement). The value is
calculated in the same way for either system. The residual pressure (page 12) is not added to or subtracted from
this value.
QUICK REFERENCE: P4, FULL TANK HYDROSTATIC PRESSURE
Px Name Description Value Range Notes
P4
Full Tank
Hydrostatic
Pressure
The pressure created by a full
column of fluid from the floor of
the tank to the top of the
maximum level to be measured. 0 to 9,999 (Keypad)
0 to 19,999 (Serial)
Pressure in
inH
2
O
@20
°C.
STEP BY STEP: P4, FULL TANK HYDROSTATIC PRESSURE
The process of programming this register is exactly the same as other real-value programmable registers. Please
refer to that procedure on page 12.
1 When the specific volume is known, perform the calculation in a similar manner, but use the inverse of the specific
volume instead of the specific gravity.
2 For non-linear tanks, use the lowest point of the tank when figuring the full distance.
All Models