简要说明：222牌的FBI’ FIRST-OUT BY-PASS INDICATOR产品：估价：1，规格：FBI’ FIRST-OUT BY-PASS INDICATOR，产品系列编号：13074884504

　　‘FBI’ FIRST-OUT BY-PASS INDICATOR
INSTALLATION
CONNECTION 1/4" FNPT
PANEL MOUNT 1 1/4" Diameter Hole
 
PORT A Instrument Pressure Inlet 30-100 PSI (2.06-6.89 bar)
PORT B Supply Pressure Inlet 30-100 PSI (2.06-6.89 bar)
PORT C Supply Pressure Outlet
PORT D Exhaust
PORT B to C By-Pass Mode
 
OPERATION
The BWB "FBI" is a 3 way, normally closed, first-out indicating relay with an integral by-pass feature. It
is normally installed in a control panel and is used to indicate the first component in which a malfunction or
unsafe condition has occurred. Using a series type hook-up, the relay receives supply pressure (Port B) from
a master relay and instrument pressure (Port A) from a safety system component such as a sensing device.
During normal operation, the master relay is pulled to the open position. This allows instrument
pressure (Port A) to push the stem into the up position and indicate in-service (green) on the indicator lens.
This also allows supply pressure (Port B) to pass through outlet (Port C) and on to the system.
 
When the sensing device is actuated, it will bleed the instrument pressure (Port A) from the relay,
causing the supply pressure (Port B) to push the stem into the down position and indicate out-of-service (red)
on the indicator lens. Supply pressure (Port B) becomes blocked, while the outlet (Port C) is exhausted (Port
D), thus closing the master relay and the system. All of the other
"FBI's" in the system will remain in the in-service (green) position, therefore giving a visual indication (red) of
the initial malfunction or unsafe condition.
 
When the need for by-pass arises, the by-pass handle must be manually pulled to the by-pass position.
Supply pressure (Port B) passes through the integral by-pass feature to the supply pressure outlet (Port C).
Loss of instrument pressure (Port A) will cause the relay to shift - indicate red on the indicator lens, but will not
affect the by-pass feature - output to the supply pressure outlet (Port C). The master relay which provides
supply pressure to the series must be closed in order to exhaust (Port D) the supply pressure outlet (Port C).
 
To resume the normal operating condition of the indicator, the by-pass handle must be manually pulled
to the normal position.
 
FEATURES
Eliminates the need to purchase an additional by-pass valve or fittings.
Can be used for Transmitting or Receiving.
 
Options FBI4 (FBI – Aluminum Body) FBI4SS (FBI – Sta