I'm reviewing a project that is going to retrofit an existing sewage lift station that is installed at the end of a hallway. The lift station serves a small section of offices and pumps wastewater out to an on-site septic system. The project will be cutting the top off of the old tank and installing a new plastic tank with Class I Div 1 rated submersible grinder pumps. The pumps come with an integrated flexible cord. There is also a set of intrinsically safe floats with integrated flexible cords.
The package came with cord connectors to get the power and control cables through the top of the tank. We will need to tap the plastic top of the tank or install a bulkhead fitting for the cord connectors. The control cable connector is CID2 listed, the power cable connector is not listed but is pressure rated.
Control Connector: https://hubbellcdn.com/specsheet/WIRING_SHC1023CR_spec.pdf
Power Connector: https://www.sealconusa.com/products...relief-fittings/nylon/standard/npt/cd21nr-bk/
A four cable cord seal was included for the float cables: http://www.sjerhombus.com/uploads/SJE_Cord_Seal_Features.pdf
Do cord connectors for flex cable at the boundary of a CID1 space need to be approved for CID1 spaces per 501.10(A)(3)? These fittings will be primarily outside of the boundary but their edge will be touching it. Their purpose it just to support the cable and seal the boundary. If bulkhead fittings are used for connecting the cord connectors would they need to be CID1 approved?
The engineer is looking at classifying the space based on NFPA 820 Figure A.4.2 with the wet well being CID1 and the 'physically separated' room being unclassified. However since there is piping connections an a removable access hatch on the top of the tank this figure doesn't appear to apply to our situation. Reading over NFPA 820 Table 4.2.2 Row 16 'Wastewater Pumping Station Wet Well' or Row 11 'Residential wastewater pumping station wet well' look like the appropriate examples. The upper left diagram in Figure A.4.2(c) looks like the proper diagram even though it doesn't show the wet well being installed in a building. But even this seems over classified for the service. It isn't a residential system but the function is the same. This lift station serves six offices and around 10 people throughout the day. NFPA 4.1.2 states 'this chapter shall not apply to on-site systems' so I think we have some leeway in choosing a fit for purpose classification. Would it be appropriate to classify the space per Table 4.2.2 Row 10 and Figure A.4.2(b) as Class I Div 2?
The package came with cord connectors to get the power and control cables through the top of the tank. We will need to tap the plastic top of the tank or install a bulkhead fitting for the cord connectors. The control cable connector is CID2 listed, the power cable connector is not listed but is pressure rated.
Control Connector: https://hubbellcdn.com/specsheet/WIRING_SHC1023CR_spec.pdf
Power Connector: https://www.sealconusa.com/products...relief-fittings/nylon/standard/npt/cd21nr-bk/
A four cable cord seal was included for the float cables: http://www.sjerhombus.com/uploads/SJE_Cord_Seal_Features.pdf
Do cord connectors for flex cable at the boundary of a CID1 space need to be approved for CID1 spaces per 501.10(A)(3)? These fittings will be primarily outside of the boundary but their edge will be touching it. Their purpose it just to support the cable and seal the boundary. If bulkhead fittings are used for connecting the cord connectors would they need to be CID1 approved?
The engineer is looking at classifying the space based on NFPA 820 Figure A.4.2 with the wet well being CID1 and the 'physically separated' room being unclassified. However since there is piping connections an a removable access hatch on the top of the tank this figure doesn't appear to apply to our situation. Reading over NFPA 820 Table 4.2.2 Row 16 'Wastewater Pumping Station Wet Well' or Row 11 'Residential wastewater pumping station wet well' look like the appropriate examples. The upper left diagram in Figure A.4.2(c) looks like the proper diagram even though it doesn't show the wet well being installed in a building. But even this seems over classified for the service. It isn't a residential system but the function is the same. This lift station serves six offices and around 10 people throughout the day. NFPA 4.1.2 states 'this chapter shall not apply to on-site systems' so I think we have some leeway in choosing a fit for purpose classification. Would it be appropriate to classify the space per Table 4.2.2 Row 10 and Figure A.4.2(b) as Class I Div 2?