GF42.25-W-2001A | Pneumatic front axle brake circuit, function | 18.6.07 |
MODEL 944, 950.5 /6, 952.5 /6, 953.6, 954.5
with CODE (BB1) Brake control (BS)
except CODE (ZX2) EPB II
MODEL 944, 950.5 /6, 952.5 /6, 953.6, 954.5
with CODE (BB8) Brake control (BS) with ASR
except CODE (ZX2) EPB II
MODEL 950.0 /1 /2 /3, 952.0 /1 /2 /3, 953.1 /3, 954.0 /1 /2 with CODE (BB1) Brake control (BS)
MODEL 950.0 /1 /2 /3, 952.0 /1 /2 /3, 953.1 /3, 954.0 /1 /2 with CODE (BB8) Brake control (BS) with ASR
W42.25-0011-12
1.1 Proportioning valve
1.2 Relay valve
13.05 Brake value sensor
16.07 Proportioning relay valve
20.02 Single-circuit diaphragm brake cylinder
V1 Supply, circuit 1
V2 Supply, circuit 2
a Supply pressure (V1 and V2)
b Redundancy circuit (pneumatic control pressure)
c Brake pressure
When the brake value sensor (13.05) is actuated, the proportioning relay valve (16.07) is electrically actuated directly by the BS/EPB control unit using the specified deceleration signal. The proportioning valve (1.1) converts the electric signal into a control pressure for the relay valve (1.2) and causes this valve to apply the brake pressure at the front axle.
The redundancy-circuit pneumatic control pressure modulated directly by the brake value sensor (13.05) is applied at the proportioning valve (1.1).
The electropneumatic brake pressure regulation has priority over the redundancy circuit.
The pneumatic control pressure of the redundancy circuit only takes over regulation of the proportioning valve (1.1) if the electric brake pressure regulation fails.
Brake application at front axle, function | Model 954.00/01/03 up to vehicle ident. end no. 279038 | ||
Model 954.00/01/03 as of vehicle ident. end no. 279039 | |||
Model 944, 950, 952, 953, 954.04/05/06/08/1/2/5 | |||
Brake application on pneumatic failure of front axle brake circuit, function | Model 944.03/23, 950.22/62, 954.00/01/03/04/22/53 |