2
INSTALLATION
A.
General
Tubing and fittings used to connect the relay must
be free of chips, dirt, and moisture or other
foreign material.
It is recommended that an "anti-seize" type thread
compound be applied to the second or third male
thread in moderate amount. Do not allow
compound to be deposited inside the relay. Thread
sealing tape is not recommended.
For continuous, trouble-free operation, the supply
to the relay must be clean and dry.
DIMENSIONS
B. Mounting
When installing the No. 83939-D Series Relay,
care should be taken to prevent any foreign matter
from entering the ports. Provisions should be
made to prevent foreign matter from entering the
ports which are left open to the atmosphere.
The relay may be installed in any position, but
vertical (upright) is recommended. The relay
should be securely mounted, using the two slots
(clearance for No. 10 screws), provided in the
mounting bracket (See Figure 1).
Figure 1
OPERATION
With no pressure applied to the diaphragm through
Port 1, Port C is connected through a hollow stem to
Port V while closed to Port S (supply port).
When sufficient pressure is applied to the diaphragm
through Port 1, the hollow stem moves down, closing
Port C to Port V. As the hollow stem moves farther, it
forces the lower poppet down opening Port S to Port
C.
Loss of the pressure at Port 1 will allow the hollow
stem to return to its original position. This allows the
spring and the supply pressure to push the lower
poppet to its original position. Port S is now closed to
Port C while Port C is connected to Port V.
The 83939-D22 and 83939-D32 have an internal
orifice assembly which connects Port 1 to Port C.
The 83939-D23 and 83939-D33 have an internal
orifice assembly which connects Port 1 to Port S.
Figure 2
