FSS – H35 Refueling protocol

If the ambient temperature exceeds 26 °C, the H35 Dispenser module cannot refuel Light Duty Vehicles (passenger cars/vans)  due to possible overshoot of the maximum working temperature of the CHSS (85 °C). In case of IR communication, the tank volume can be checked to make sure no LDV will be refueled by the H35 Dispenser module at ambient temperature ≥ 26 °C.

In case there is no IR communication, the tank volume can be calculated by performing multiple pulses and calculate density increase using pressure before- and after pulse. If the tank volume is lower than the max. volume of vehicle capacity category C (248,6 l or 10 kg), the refueling must be aborted. Otherwise, the refueling can be continued conform the protocol.

Refuelling of Heavy-Duty Vehicles (busses/trucks) with a valid data connection established from vehicle to fueling station dispenser as described in SAE J2799 is performed by the H35 Protocol table as shown in Table 1.

Boundaries to the H35 Com refueling protocol are:

• The maximum allowable P_nozzle is 43,8 MPa.
• The maximum allowable IR_pressure is 43,8 MPa.
• Maximum allowable IR_Temperature is 85 °C.
• Maximum allowable SOC is 100%
• Upper pressure tolerance/limit of PRR_Target + 7MPa is exceeded more than 5 seconds.
• Lower pressure tolerance/limit of PRR_Target – 2 MPa is exceeded more than 15 seconds.

If one of the boundaries above is achieved during the refueling, the dispenser shall stop the refueling process as soon as possible, but within 5 seconds. These boundaries are in accordance with the SAE J2601/SAE J2601-2.

Refuelling of Heavy-Duty Vehicles without a valid data connection established from vehicle to fueling station dispenser as described in SAE J2799 is performed by the H35 Protocol table as shown in Table 1.

While for H35 communication refueling there is no set P_target, for H35 non-communication refueling a P_target is applicable depending on ambient temperature and initial tank pressure (P₀).

Boundaries to the H35 Non-com refueling protocol are:

• The maximum allowable P_nozzle is 43,8 MPa.
• The target pressure (P_target) is set conform Table 2.
• Upper pressure tolerance/limit of PRR_Target + 7MPa is exceeded more than 5 seconds.
• Lower pressure tolerance/limit of PRR_Target – 2 MPa is exceeded more than 15 seconds.

If one of the boundaries above is achieved during the refueling, the dispenser shall stop the refueling process as soon as possible, but within 5 seconds. These boundaries are in accordance with the SAE J2601/SAE J2601-2.