Backfeed Box Installation
For Easy UPS 3S, Easy UPS 3S Pro, and Easy UPS 3M
Model Numbers: SP3OPT008, SP3OPT009, SP3OPT010
Latest updates are available on the Schneider Electric website
Publication Date: 7/2025
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Important Safety Instructions
Read these instructions carefully and look at the equipment to become familiar with it before trying to install, operate, service or maintain it. The following safety messages may appear throughout this manual or on the equipment to warn of potential hazards or to call attention to information that clarifies or simplifies a procedure.
DANGER indicates a hazardous situation which, if not avoided, will result in death or serious injury.
WARNING indicates a hazardous situation which, if not avoided, could result in death or serious injury.
CAUTION indicates a hazardous situation which, if not avoided, could result in minor or moderate injury.
NOTICE is used to address practices not related to physical injury.
Electrical equipment should only be installed, operated, serviced, and maintained by qualified personnel. Schneider Electric assumes no responsibility for any consequences arising out of the use of this material.
A qualified person is one who has skills and knowledge related to the construction, installation, and operation of electrical equipment and has received safety training to recognize and avoid the hazards involved.
Safety Precautions
DANGER: HAZARD OF ELECTRIC SHOCK, EXPLOSION, OR ARC FLASH
- Read all instructions in the installation manual before installing or working on this product.
- Do not install the product until all construction work has been completed and the installation room has been cleaned.
- The product must be installed according to the specifications and requirements as defined by Schneider Electric, including external and internal protections (upstream breakers, battery breakers, cabling, etc.) and environmental requirements. Schneider Electric assumes no responsibility if these requirements are not respected.
- The UPS system must be installed according to local and national regulations, including but not limited to: IEC 60364, NEC NFPA 70, or Canadian Electrical Code (C22.1, Part 1).
- Install the product in a temperature-controlled indoor environment free of conductive contaminants and humidity.
- Install the product on a non-flammable, level, and solid surface (e.g., concrete) that can support the weight of the system.
- The product is not designed for and must not be installed in environments with: damaging fumes; explosive mixtures of dust or gases; corrosive gases; conductive or radiant heat; moisture; abrasive dust; steam; excessively damp conditions; fungus; insects; vermin; salt-laden air; contaminated cooling refrigerant; pollution degree higher than 2 (IEC 60664-1); abnormal vibrations, shocks, or tilting; direct sunlight; heat sources; or strong electromagnetic fields.
- Do not drill or cut holes for cables or conduits with the gland plates installed, and do not drill or cut holes in close proximity to the UPS system.
- Do not make mechanical changes to the product (including removal of cabinet parts or drilling/cutting of holes) that are not described in the installation manual.
NOTICE: RISK OF OVERHEATING
- Respect the space requirements around the product and do not cover the ventilation openings when the product is in operation.
Electrical Safety
DANGER: HAZARD OF ELECTRIC SHOCK, EXPLOSION, OR ARC FLASH
- Electrical equipment must be installed, operated, serviced, and maintained only by qualified personnel.
- Apply appropriate personal protective equipment (PPE) and follow safe electrical work practices.
- Disconnection devices for AC and DC must be provided, readily accessible, and marked for their function.
- Turn off all power supplying the UPS system before working on or inside the equipment.
- Before working on the UPS system, check for hazardous voltage between all terminals, including the protective earth.
- The UPS contains an internal energy source. Hazardous voltage can be present even when disconnected from the mains supply. Ensure units are OFF and mains and batteries are disconnected. Wait five minutes before opening the UPS to allow capacitors to discharge.
- The UPS must be properly earthed/grounded. Due to high touch current/leakage current, the earthing/grounding conductor must be connected first.
Specifications
Backfeed Contactor Specifications
DANGER: HAZARD OF ELECTRIC SHOCK, EXPLOSION OR ARC FLASH
The SP3OPT008, SP3OPT009, and SP3OPT010 must only be used with the UPSs listed in the compatibility matrices below.
Easy UPS 3S Compatibility Matrix
| UPS rating | Easy UPS 3S 3:1 | Easy UPS 3S 3:3 | |
| Single mains system | Input | 1 x SP3OPT009 | 1 x SP3OPT008 |
| Input current limitation (A) | 65 A, 3 phases (input current limitation) 172 A, 1 phase (bypass current)(1) | 89 A, 3 phases | |
| Dual mains system | Input | 1 x SP3OPT008 | 1 x SP3OPT008 |
| Input current limitation (A) | 65 (3 phases) | 89 (3 phases) | |
| Bypass | 1 x SP3OPT009 172 (1 phase) | 1 x SP3OPT008 77 (3 phases) |
(1) Current includes the overload capacity of 125% continuous for Easy UPS 3S in static bypass mode.
Easy UPS 3S Pro Compatibility Matrix
| UPS rating | Easy UPS 3S Pro 3:3 | |
| Single mains system | Input | 1 x SP3OPT008 |
| Input current limitation (A) | 81 A (3 phases) | |
| Dual mains system | Input | 1 x SP3OPT008 |
| Input current limitation (A) | 81 A (3 phases) | |
| Bypass | 1 x SP3OPT008 67 A (3 phases) |
Easy UPS 3M Compatibility Matrix
| UPS rating | Easy UPS 3M 3:3 | ||||||
| 60 kVA | 80 kVA | 100 kVA | 120 kVA | 160 kVA | 200 kVA | ||
| Single mains system | Input | 1 x SP3OPT009 | 1 x SP3OPT009 | 1 x SP3OPT009 | 1 x SP3OPT010 | 1 x SP3OPT010 | 1 x SP3OPT010 |
| Input current limitation (A) | 155 | 206 | 258 | 309 | 412 | 515(2) | |
| Dual mains system | Input | 1 x SP3OPT009 | 1 x SP3OPT009 | 1 x SP3OPT009 | 1 x SP3OPT010 | 1 x SP3OPT010 | 1 x SP3OPT010 |
| Input current limitation (A) | 155 | 206 | 258 | 309 | 412 | 515(2) | |
| Bypass | 1 x SP3OPT009 | 1 x SP3OPT009 | 1 x SP3OPT009 | 1 x SP3OPT010 | 1 x SP3OPT010 | 1 x SP3OPT010 | |
| Bypass current (A) | 91 | 122 | 152 | 184 | 246 | 307 |
(2) 515 A at operating temperature of 0 °C to 30 °C. Maximum 450 A at operating temperature of 30 °C to 40 °C.
Power Contactor Specifications
| SP3OPT008 | SP3OPT009 | SP3OPT010 | |
| Power contactor | 95 A, 3P LC1D95V7; AC3 duty 95 A | 275 A, 3P LC1G150LSEA, AC1 duty 275 A | 550 A, 3P LC1G400LSEA, AC1 duty 550 A |
| Rated operational voltage | Refer to the UPS installation manual for rated UPS operational voltage. | ||
| Coil operating voltage | 320-440 VAC | 200-500 VAC | 200-500 VAC |
| Frequency (Hz) | 50/60 | ||
| Short circuit capacity | 10 kA Icc conditioned by the upstream protection listed in the UPS installation manuals. | ||
| Earthing system | TNS - TT. Not compatible with IT earthing system where 4 pole contactor is required. | ||
Recommended Upstream Protection
Refer to the UPS installation manual for recommended upstream protection.
Recommended Cable Sizes
NOTE: Aluminum cables are not supported.
Refer to the UPS installation manual for recommended cable sizes.
Recommended Bolt and Lug Sizes (Copper)
| Cable size | Bolt size | Cable lug type |
| 16 mm² | M8 | KST TLK16-8 |
| 25 mm² | M8 | KST TLK25-8 |
| 35 mm² | M8 | KST TLK35-8 |
| 50 mm² | M10 | KST TLK50-10 |
| 70 mm² | M10 | KST TLK70-10 |
| 95 mm² | M10 | KST TLK95-10 |
| 120 mm² | M10 | KST TLK120-10 |
| 150 mm² | M10 | KST TLK150-10 |
Torque Specifications
| Bolt size | Torque |
| M4 | 1.7 Nm |
| M5 | 2.2 Nm |
| M6 | 5 Nm |
| M8 | 17.5 Nm |
| M10 | 30 Nm |
| M12 | 50 Nm |
Backfeed Box Weights and Dimensions
| Commercial reference | Weight kg | Height mm | Width mm | Depth mm |
| SP3OPT008 | 20 | 300 | 550 | 200 |
| SP3OPT009 | 33 | 600 | 600 | 250 |
| SP3OPT010 | 58 | 800 | 700 | 400 |
Environment
| Operating | Storage | |
| Temperature | SP3OPT008 and SP3OPT009: 0 °C to 40 °C. SP3OPT010: 0 °C to 30 °C. Operation at 30 °C to 40 °C at maximum 450 A. | -25 °C to 55 °C |
| Relative humidity | 0-95% non-condensing | 0-95% non-condensing |
| Elevation | Designed for operation in 0-2000 m | |
| Protection class | IP20 | |
| Color | RAL 9003, 85% gloss |
Installation Procedure
Single Mains System Diagram
A diagram shows a UPS connected to a Backfeed box (input), with a load connected to the UPS. A signal cable and a power cable are indicated.
Dual Mains System Diagram
A diagram shows a UPS connected to a Backfeed box (input) and a Backfeed box (bypass). The UPS is connected to the load and bypass. A signal cable and a power cable are indicated.
Installation Steps:
- Mount the Backfeed Box to the Wall (page 13).
- Prepare the Backfeed Box for Cables (page 15).
- Connect the Input Power Cables to the Input Backfeed Box (page 17).
- For dual mains systems only: Perform one of the following:
- Connect the Bypass Power Cables to the Bypass Backfeed Box for 3:1 System (Dual Mains System Only) (page 19).
- Connect the Bypass Power Cables to the Bypass Backfeed Box for 3:3 System (Dual Mains System Only) (page 21).
Mount the Backfeed Box to the Wall
CAUTION: RISK OF INJURY OR EQUIPMENT DAMAGE
- Mount the backfeed box to a wall or a rack that is structurally sound and able to support the weight of the unit.
- Use appropriate M10 hardware (not supplied) to mount the backfeed box to the wall.
Instructions:
- Measure and mark the four mounting hole locations on the wall.
SP3OPT008 Mounting Diagram
A diagram shows the SP3OPT008 backfeed box with dimensions for mounting holes: 400 mm width, 338 mm height, with M10 Ø12 mm mounting holes.
SP3OPT009 Mounting Diagram
A diagram shows the SP3OPT009 backfeed box with dimensions for mounting holes: 450 mm width, 638 mm height, with M10 Ø12 mm mounting holes.
SP3OPT010 Mounting Diagram
A diagram shows the SP3OPT010 backfeed box with dimensions for mounting holes: 550 mm width, 638 mm height, with M10 Ø12 mm mounting holes.
Continued Instructions:
- Drill holes in each of the four marked locations.
- Mount the backfeed box to the wall.
Prepare the Backfeed Box for Cables
DANGER: HAZARD OF ELECTRIC SHOCK, EXPLOSION, OR ARC FLASH
- Do not drill or punch holes for cables or conduits with the gland plates installed, and do not drill or punch holes in close proximity to the product.
Illustrations show SP3OPT008. The procedure is the same for SP3OPT009 and SP3OPT010.
- Open the front door.
- Remove the screws and the front plate.
Diagram: A diagram shows the inside of the backfeed box with arrows indicating the removal of the front plate.
- Remove the gland plate.
Diagram: A diagram shows the inside of the backfeed box with arrows indicating the removal of the gland plate.
- Drill or punch holes for cables or grommets/conduits (not provided) in the gland plate.
- Install grommets/conduits (if applicable) and refit the gland plate.
DANGER: Ensure that there are no sharp edges that can damage the cables.
Diagram: A diagram shows the gland plate with newly punched holes and arrows indicating the refitting of the gland plate.
Connect the Input Power Cables to the Input Backfeed Box
Instructions:
- Connect the PE cables.
- Connect the UPS input cables (L1, L2, L3, N).
- Connect the input cables (L1, L2, L3, N).
- Reinstall the front plate with the screws.
- Close and lock the front door.
SP3OPT008 (Input Only) Wiring Diagram: A diagram shows the internal wiring connections for the SP3OPT008, indicating connections for PE, L1, L2, L3, and N for both UPS input and main input.
SP3OPT009 (Input Only) Wiring Diagram: A diagram shows the internal wiring connections for the SP3OPT009, indicating connections for PE, L1, L2, L3, and N for both UPS input and main input.
SP3OPT010 (Input Only) Wiring Diagram: A diagram shows the internal wiring connections for the SP3OPT010, indicating connections for PE, L1, L2, L3, and N for both UPS input and main input.
Connect the Bypass Power Cables to the Bypass Backfeed Box for 3:1 System (Dual Mains System Only)
NOTE: Follow the UPS installation manual to remove the single mains busbars in the UPS.
Instructions:
- Connect the PE cables.
- Connect the UPS bypass cables (L1, N).
- Connect the bypass cables (L1, N).
SP3OPT009 for 3:1 System (Bypass Only) Wiring Diagram: A diagram shows the internal wiring connections for the SP3OPT009 in a 3:1 bypass configuration, indicating connections for PE, L1, L2, L3, and N for both UPS bypass and main bypass.
- Disconnect the signal cable E31 from the L2 busbar of the power contactor. Reconnect the E31 signal cable to the neutral busbar.
- Reinstall the front plate with the screws.
- Close and lock the front door.
Connect the Bypass Power Cables to the Bypass Backfeed Box for 3:3 System (Dual Mains System Only)
NOTE: Follow the UPS installation manual to remove the single mains busbars in the UPS.
Instructions:
- Connect the PE cables.
- Connect the UPS bypass cables (L1, L2, L3, N).
- Connect the bypass cables (L1, L2, L3, N).
- Reinstall the front plate with the screws.
- Close and lock the front door.
SP3OPT008 for 3:3 System (Bypass Only) Wiring Diagram: A diagram shows the internal wiring connections for the SP3OPT008 in a 3:3 bypass configuration, indicating connections for PE, L1, L2, L3, and N for both UPS bypass and main bypass.
SP3OPT009 for 3:3 System (Bypass Only) Wiring Diagram: A diagram shows the internal wiring connections for the SP3OPT009 in a 3:3 bypass configuration, indicating connections for PE, L1, L2, L3, and N for both UPS bypass and main bypass.
SP3OPT010 for 3:3 System (Bypass Only) Wiring Diagram: A diagram shows the internal wiring connections for the SP3OPT010 in a 3:3 bypass configuration, indicating connections for PE, L1, L2, L3, and N for both UPS bypass and main bypass.
Backfeed Box One Line Drawing
Instructions to end user:
- Easy UPS backfeed box having a rated conditional short-circuit current not exceeding 10 kA r.m.s.
- Easy UPS backfeed box shall be protected by current-limiting devices having a cut-off current not exceeding 17 kA with the maximum allowable prospective short-circuit current at the terminals of the incoming circuit of the ASSEMBLY.
Single Mains UPS (3:1) Diagram: A one-line diagram illustrates the connection of a primary power source to a backfeed box (SP3OPT009), then to a UPS (Easy UPS 3S 3:1 Single Feed), and finally to the load. It includes notes about contactor and upstream installation ratings and applicability to IT earthing systems.
Dual Mains UPS (3:1) Diagram: A one-line diagram illustrates the connection of a primary power source to a backfeed box (SP3OPT008), then to a UPS (Easy UPS 3S 3:1 Dual Feed), and finally to the load. It also shows a second backfeed box (SP3OPT009) connected to the bypass. It includes notes about contactor and upstream installation ratings and applicability to IT earthing systems.
Single Mains UPS (3:3) Diagram: A one-line diagram illustrates the connection of a primary power source to a backfeed box, then to a UPS (Easy UPS 3S Single Feed), and finally to the load. It includes notes about contactor and upstream installation ratings and applicability to IT earthing systems.
Dual Mains UPS (3:3) Diagram: A one-line diagram illustrates the connection of a primary power source to a backfeed box, then to a UPS (Easy UPS 3S Dual Feed), and finally to the load. It also shows a second backfeed box connected to the bypass. It includes notes about contactor and upstream installation ratings and applicability to IT earthing systems.
