012696 GL0011P-07
– Installation Guidelines for BioDisc BA, BAx, BB & NB Units
Page 6
1.3.10 BioDisc units must be installed at a level which will allow connection to the incoming drain and a free
discharge at the system outlet (excepting units with an integral discharge pump). Effluent pumping
stations are available to lift the discharge to a higher level and/or pump to remote discharge points.
1.3.11 The unit should be installed so that the bottom lip of the cover is 95mm above local ground level. If
the unit has to be recessed, measures must be taken to ensure that it cannot be flooded by surface
water run-off.
1.3.12 It is essential that all surface water be segregated and excluded from entering the treatment plant.
1.3.13 BioDisc covers are not suitable for walking on. Where necessary the BioDisc should be fenced off or
otherwise protected. Maintenance access must be maintained as above.
1.3.14 The drainage system connecting to the BioDisc must be adequately vented in accordance with the
Building Regulations. The head of the drainage system should be connected to a stack pipe, open at
high level, so as to draw foul air from the system and sited with consideration to prevailing wind
direction. Tile vents & Air admittance valves should not be used as the sole drainage ventilation
facility, but if this cannot be avoided, the BioDisc should be independently ventilated. All inspection
points within the drain system should be sealed so as to enable ventilation at high level.
1.3.15 An adequate electrical supply must be provided, complying with current electrical regulations. The
electrical details in Table 1 will enable selection of suitable cable and current overload protection,
taking into account the distance from the power source to the control panel and any other relevant
factors. In most cases steel wire armoured (SWA) cable, minimum 1.5sq mm will be suitable,
selection of the cable is the responsibility of the installing electrician.
Full Load Current (Amps)
BA
BAx
BB
NB
Motor
240 volt single phase
0.52
0.52
0.52
0.52
415 volt three phase
0.22
0.22
0.22
0.22
Integral discharge pump
240 volt single phase only
2.2
2.2
2.2
N/A
Sludge return pump
240 volt single phase only
N/A
N/A
N/A
2.2
Table 1 : Electrical Supply Data
1.3.16 Residual Current Device (RCD) protection is required for BioDisc units fitted with an integral
discharge pump. RCD protection is not obligatory for BioDisc units without a discharge pump, but is
suggested as an extra precaution.
1.3.17 Independent pump stations or any other associated equipment should have a separate power
supply.
1.3.18 Proximity to a mains water hose pipe connection point is recommended, for maintenance purposes.
Such a supply should be connected in accordance with water bylaws and regulations.
Never leave a
hose connected and immersed in sewage.
1.3.19 Installation should only be carried out by suitably qualified and experienced contractors in
accordance with the Health and Safety at Work Act. Electrical work should be carried out by a
qualified electrician, working to the latest edition of IEE.
2
Installation - General
2.1.1
When units are installed in unstable ground conditions where movement of the surrounding material
and/or unit may occur, the connecting pipework should be designed to minimise the risk of damage
from differential movement of the unit(s) and/or surrounding material.
2.1.2
In situations where the excavation will not maintain a vertical wall, it will be necessary to support side
walls of the excavation (e.g. with suitable trench sheets and bracing systems) to maintain a vertical
wall from the bottom to the top of the excavation. DO NOT completely remove the shoring system
until after the back-filling is complete, but before the concrete fully hardens.
2.1.3
In areas where the water table is above the bottom of the excavation and/or the excavation is liable
to flood, the excavation should be de-watered, using suitable pumping equipment, until the
