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SD62
INSTALLATION
Shipping and Storage
If the relay is to be stocked, stored, or shipped to another location prior to piping, make sure that the factory
installed plastic plugs are in the ports to prevent entry of moisture, dirt, or other contaminants.
Mounting
Mounting dimensions and the locations and sizes of the pipe connections are shown in Figures 1 and 2. Connect the
inlet to a filtered air supply of at least 5 psi greater than the maximum process pressure (including the liquid head). It
is not necessary that the supply pressure be regulated although this is generally preferable. A filter in the supply line
is very desirable as it will minimize possible clogging of the needle valve. See Instrument Air Requirements below.
Blow out all piping before connections are made to prevent the possibility of dirt or chips entering the relay. Use
pipe sealant sparingly, and then only on the male threads. A non-hardening sealant is strongly recommended.
Exceeding the specified ambient temperature limits can adversely affect
performance and may cause damage to the instrument.
Supply pressure in excess of 150 psig may cause damage to the instrument.
Figure 3 shows an application example. The piping between the end of the dip tube and the junction of the
instrument connection to the bubbling line should be kept as short as possible and should be at least 1/4" pipe or
larger. For example: At a flow rate of 0.9 SCFH, the pressure drop in a 20-foot length of 1/4" pipe will not exceed
0.20" H
0 head but approximately ten times this drop would be obtained with 1/4" O.D. tubing. Pressure drop
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between the relay and the junction of the receiving instrument is ordinarily of no consequence, so that this line may
be made any desired size.
Instrument Air Requirements
Connect the instrument to a source of clean, dry. oil-free instrument air. Failure to do so will Increase the possibility
of a malfunction or a deviation from specified performance.
Use of process fluids other than instrument air is not recommended. No claim is made as to
the suitability of this product for use with other process fluids, such as hazardous gases,
except as listed on the appropriate certificate. Non-approved instruments are suitable for use
with instrument air only. Optional features and modifications such as tapped exhaust do not
imply suitability for use with hazardous gases except as listed on the approval certificate.
There are many types of synthetic compressor lubricants. Some may not be compatible with the materials used in
construction of the instrument – see the list of materials on page 1. Wetting of these materials by such an oil mist or
vapor, etc., may cause them to deteriorate. This may ultimately result in failure of the positioner.
Synthetic compressor lubricants in the air stream at the instrument may cause it to fail.
CAUTION
CAUTION
CAUTION
CAUTION
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