Meriam MANOMETERS - Manual

5. Connections to Process
It is necessary that the instrument be properly connected to the
system in order to obtain a significant and accurate indication. All
connections must be leak-free.
U-Tube Manometers — Either high or low pressure may be con-
nected to either side of the instrument, provided that the difference
between them is within the indicating range of the instrument.
Well & Inclined Tube Manometers — Vertical and incline tube
manometers require more careful consideration. Basically, the
indicating fluid will move towards the low pressure and away
from the high pressure, until a hydrostatic balance has been
reached. In many cases it is possible that atmospheric pressure can
be considered as the high pressure. By noting the liquid level in
the filled manometer, it is possible to deduce whether the visible
level should be moved up or down to produce visible readings. By
knowing which of the two pressures is greater (as measured from
zero psia), the proper choice of meter connections can be made. It
may be noted that in flow metering work using orifice plates the
upstream pressure is greater than the downstream. For pitot tubes
the impact pressure is greater than the static pressure.
General Installation, Operation & Maintenance Instructions for
MERIAM MANOMETERS
1. Uncrating & Inspection
Carefully unpack the instrument. Make a thorough check for pos-
sible shipping damage. Remove all protective cushions or plugs. If
damaged, notify carrier and Meriam of damage. Be certain all items
on packing list are removed from container.
2. Mounting
Mount the instrument at a convenient height for reading vertically
on wall, panel, or table depending on mounting style. Be certain
instrument is level. Check with level on side and front of instrument
case. If instrument is furnished with a built-in level, use it to insure
level mounting. Table mounting stands are shipped separate from
instruments. Therefore attach the stand to the instrument.
3. Scale Adjustment (most models)
Position the scale at the center of the adjustment span.
4. Filling
U-Tube Manometers — Remove the top manometer head or fill
plug. Be sure instrument is properly vented on the low pressure
side. Slowly pour the selected manometer indicating fluid into the
glass tube until the indicating fluid level is at approximately the zero
graduation on the scale. Be sure all air bubbles are eliminated. Re-
place the head tightly. Adjust the scale for the correct zero position
in relation to the indicating fluid meniscus.
Well Type Manometers — Remove the fill plug on the well. Be
sure instrument is properly vented on the low pressure side. Slowly
pour the selected manometer indicating fluid into the well until the
indicating fluid level is at approximately the zero graduation on the
scale. Be sure all air bubbles are eliminated. Replace the fill plug
tightly. Adjust the scale for the correct zero position in relation to
the indicating fluid meniscus.
Inclined Tube Manometers — Remove the fill plug. Be sure to
check the instrument scale before filling to be certain the correct
indicating fluid is being used. Most inclined tube manometers use
Meriam 827 Red Oil or Meriam 1000 Green Concentrate. For ac-
curate measurements, it is critical to have the correct indicating fluid
in the instrument! Be sure instrument is properly vented on the low
pressure side. Slowly pour the selected manometer indicating fluid
into the well until the indicating fluid level is at approximately the
zero graduation on the scale. Be sure all air bubbles are eliminated.
Replace the fill plug tightly. Adjust the zero position by adjusting
the scale or the zero adjustment knob on the well, depending on the
model involved.
** THESE INSTRUMENTS MAY CONTAIN MERCURY.
PLEASE RECYCLE OR DISPOSE AS HAZARDOUS
WASTE ACCORDING TO LOCAL, STATE, AND FEDERAL
REGULATIONS. Consult Material Safety Data Sheets (MSDS)
for handling information and safety data.
Instruction Sheet
F/N: 022C:440-14
E.O. # 5946