TM 55-2210-224-34
4-16. H-5 RELAY AIR VALVE (cont)
TEST
25.
Test the H-5 relay air valve in accordance with New
York Air Brake Company Test Specification NYT-
408-C. The H-5 relay air valve functions as follows:
a.
When control port 10 is not pressurized, the
diaphragm and spool valve are held in the
upper position by a return spring. Non of the
ports are in communication at this time.
b.
When control port 10 is pressurized sufficiently
to move the spool against the force of the
return spring, port 11 is in communication with
port 9, which is exhausted. Port 12 is still
blocked off.
4-87