Baxi ECOGEN 24/1.0, Installation & Servicing Instructions Manual

Page: 16 / 94

(i) The basic design parameters for the circuit are:
I
b >
I
g where
I
b is the design current and Ig is the rated output current of the Ecogen
I
n >
I
b where In is the nominal current of the overload protective device
Disconnection of the final circuit in the event of an earth fault on the circuit and de­energising of the Ecogen should both occur within an overall maximum time of
0.4 s for TN systems and 0.2 s for TT systems. However, if the protective device for automatic disconnection in case of an earth fault disconnects line and neutral
conductors, it is not necessary to take account of the time taken for the Ecogen to de­energise.
(ii) Where an Ecogen is connected on the same side of an RCD as final circuits protected by that RCD, the RCD must disconnect the line and neutral conductors.
(iii) The Ecogen must be provided with means of isolation and of switching off for mechanical maintenance.
16. Connection of a Ecogen to an existing final circuit
(i) The basic design parameters for the circuit are:
I
z >
I
n+
I
g where
I
z is the current carrying capacity of the conductors of the final circuit, In is the nominal current of the overload protective device and
I
g is the rated
output current of the Ecogen. This may require the protective device to be replaced with one having a lower nominal current rating.
Disconnection of the final circuit in the event of an earth fault on the circuit and de­energising of the Ecogen should both occur within an overall maximum time of
0.4 s for TN systems and 0.2 s for TT systems. However, if the protective device for automatic disconnection in case of an earth fault disconnects line and neutral
conductors, it is not necessary to take account of the time taken for the Ecogen to de­energise.
IMPORTANT: In designing a connection for the Ecogen 24/1.0 the electrical installer
has to consider all the issues that would need to be covered for a conventional final
circuit, including:­
In Accordance with BS: 7671.
the maximum demand (and the generator output)
the type of earthing arrangement
the nature of the supply
external influences
compatibility, maintainability and accessibility
protection against electric shock
protection against thermal effects
protection against over current
isolation and switching
equipment selection and installation issues
The electrical installer should check that the prospective fault current would not
change sufficiently to exceed the fault rating of existing protective devices.
Fig. 13
Fig. 13a