Assembling the AC Field Plug

You can use the AC field plugs included in the delivery for different purposes:

  • Connecting the AC cable of the first inverter to the Sunny Multigate. However, this connection can also be made using a junction box.

  • Using two AC field plugs to bridge greater distances between two inverters. The AC cables available at SMA Solar Technology AG for connecting the inverters have a limited length ( > Spare Parts and Accessories).

Overview

875595916

Elements of the AC field plug

Position

Designation

A

Insulator

B

Enclosure

C

Seal

D

Screw connection

Additionally required material (not included in the scope of delivery):

  • Three bootlace ferrules: 2.5 mm²
  • Cable shears: 165 mm
  • Stripping knife with straight knife blade: 8 mm to 28 mm
  • Insulation stripping tool: up to 10 mm²
  • Crimping tool for bootlace ferrules: up to 10 mm²
  • Torque screwdriver: 0.3 Nm to 1.2 Nm
  • Cross-head screwdriver Pozidriv – bit, 1.4" or BiTorsion, 1/25 mm
  • Torque wrench, scale adjustable, 2 Nm to 20 Nm
  • Crow-Ring wrench, AF 25
  • Square insertion tool, outer square: 3/8", inner square: 9 mm x 12 mm
  • Screwdriver: insulated, blade width: 4 mm, blade thickness 0.8 mm

DANGER

Danger to life due to electric shock

  1. Do not disconnect or connect the AC field plug under load.
  2. Only assemble the AC field plug in a dry environment.
  3. Observe the operating temperature range of −40°C to +85°C.

Cable requirements:

  • Cable cross-section: 2.5 mm²
  • Temperature-resistant up to at least +90°C
  • External diameter of the cable sheath: 9.6 mm to 10 mm
  • Number of stranded wires: 46
  • Cable type: copper wire, tin-plated
  • Wire cross-section: 0.25 mm²

Removing and reassembling the AC field plug is only possible within 72 hours

  1. In total, the AC field plug may at maximum be removed three times and only within the first 72 hours after the first assembly.
  2. After the period of 72 hours has expired, the AC field plug must not be removed.
  3. The cable must be shortened again before each assembly.
  4. Only disconnect and disassemble the AC field plug following the instructions in this document ( > Disconnecting the AC Field Plug).

Procedure:

To assemble and connect the AC field plug, carry out the following steps in the given sequence. The exact procedure is described in the paragraphs below.

  • Assembling the Cable

  • Premounting the AC Field Plug

  • Mounting the Insulator

  • Completing Mounting of the AC Field Plug

Assembling the Cable

  1. Shorten the cable to the desired length using cable shears.
  2. Dismantle the cable by 42 mm using the stripping knife. Take care not to damage the individual insulated conductors.
  3. Shorten L and N by 7 mm.
    4. 865158028
  4. Using the insulation stripping tool, strip the insulation of the three individual conductors by 10 mm each (tolerance: ± 1 mm). Take care not to damage the individual stranded wires.
  5. The cable is assembled.
  6. Push one bootlace ferrule onto each stripped insulated conductor up to the stop.
  7. Crimp the bootlace ferrule tightly using a crimping tool.
  8. Ensure that a crimping length of max. 2.4 mm is maintained.

Premounting the AC Field Plug

  1. Slide the screw connection over the cable with the bootlace ferrules. Ensure that the thread of the screw connection is facing the bootlace ferrule.
  2. Use your fingers to push the seal as far as possible into the plug enclosure.
  3. Lead the plug enclosure with the seal over the cable. The thread must be facing the thread of the screw connection.

Mounting the Insulator

  1. Push the stranded wires with the bootlace ferrules up to the stop in the premounted pin connectors inside the insulator. The line conductor must be plugged into pin connector L, the neutral conductor into pin connector N and the grounding conductor into the pin connector with the symbol .
  2. The bootlace ferrules are no longer visible.
  3. Tighten the three screws in the insulator using a screwdriver (torque: 0.8 Nm).
  4. Make sure that the individual conductors are positioned securely in the correct pin connectors of the insulator.

Completing Mounting of the AC Field Plug

  1. Push the plug enclosure onto the insulator.
  2. Both parts snap together. The catch mechanism on the insulator and on the plug enclosure must be correctly aligned.
  3. Tighten the screw connection of the plug enclosure using a torque wrench and then tighten it with two different torques:

    • First tighten the screw connection with a torque of 3.3 Nm. Set the value 3.0 Nm at the scale of the torque wrench specified by SMA Solar Technology AG.

    • Then tighten the screw connection with a torque of 4.4 Nm. Set the value 4.0 Nm at the scale of the torque wrench specified by SMA Solar Technology AG.

    • Hint: The given torque setting only applies to the torque wrench specified by SMA Solar Technology AG. The value to be set on the torque wrench is lower than the actual value (for more information on the calculation of the torque to be set, go to www.stahlwille.com). A torque wrench consists of the following components: torque wrench (basic device), square insertion tool and crow's foot wrench.

  4. Make sure that the screw connection of the plug enclosure is securely fastened.
    <  AC Cabling of the Inverters
    >  Connecting Additional Grounding