SolarEdge S1200 Commercial Power Optimizer Long Input (1.6m)

The SolarEdge S1200 with long input (S1200-LI-MC4) is a commercial power optimiser for one or two high-power or bifacial modules, rated at 1,260 W of input. Its MC4 input leads run to 1.6 m rather than the short version's 0.1 m, letting it sit further from the module junction boxes it serves.

It works only with SolarEdge three-phase commercial inverters, tracks the maximum power point of the modules on its input at up to 99.5% efficiency, and drops to a 1 V safety output whenever the inverter is off or the string is disconnected. SolarEdge rates its output at 20 A, against 18 A for the S1000.

The S1200 long input in figures

What the 1.6 m input changes

SolarEdge's datasheet lists the S1200 with either a 0.1 m or a 1.6 m input lead; the output leads are the same on both, 5.3 m on the positive side and 0.1 m on the negative. Its installation chapter asks for each optimiser to be placed close enough to its module for the cables to connect, and it rules out extension cables between two modules wired to the same optimiser. Where the modules on one input are too far apart for 0.1 m leads to meet, the 1.6 m version is SolarEdge's own way of bridging the gap. SolarEdge publishes no layout rule for choosing between them, so measure the spacing on the racking first.

Inverters and string design

The compatible-inverter line reads all commercial three-phase inverters, and the design table names the units: SE25K, SE27.6K, SE30K and SE33.3K on a 230/400 V grid, the SE40K on 277/480 V, and Synergy units of the same ratings. The SE15K, SE16K and SE17K pairings are restricted to markets outside the UK. On an SE33.3K, Fixed String Voltage has to be switched from 750 to 850 Vdc in SetApp before S1200s will work with it.

Every string needs at least 14 optimisers, 15 on the SE30K, SE33.3K and SE40K, and no more than 30, carrying up to 60 modules. Parallel strings may differ in length or face different directions, provided the longest has no more than five optimisers more than the shortest on the same inverter unit. Per-string power limits differ by inverter, so check the design in SolarEdge Designer.

Modules on one input

The normal pairing is two modules in series on the single input, with their combined STC rating no higher than 1,260 W; modules with a power tolerance of up to +5% are accepted. A 1:1 connection is allowed only when the whole string is wired that way, or when a single optimiser in the string is the exception.

A separate application note covers two modules in parallel through branch cables, the S-Series replacement for the old dual-input P800p. Each module's Isc must be under 7.5 A and its cold-temperature Voc under 125 V, and Sense Connect does not see the branch-cable joints.

Mixing, connectors and mounting

• Mixing: the S1200 shares a string with no other optimiser model, S1000 and every P-Series included; other models must go on separate strings.
• Connectors: the supplied type is Stäubli MC4. SolarEdge strongly recommends identical connectors on module and optimiser; a non-identical pairing needs the connector maker's confirmation and a third-party test report, or connector faults fall outside warranty. Amphenol types are not supported on S-Series.
• Fixing: M6 stainless bolts, nuts and washers at 9–10 N·m, with a clutch drill or torque wrench, never an impact driver. Any orientation works; shade from direct sun is recommended, and it must not go anywhere it could end up under water.
• Cabling: cutting an input or output connector voids the warranty. Home runs on inverters above SE17K may total 700 m, in cable of at least 4 mm².

Order alongside

• S1200 Power Optimizer (Short Input 0.1m)

  The same S1200 model on 0.1 m input leads, for modules whose junction boxes sit close enough together not to need the long version.

• S1000 Power Optimizer Long Input (1.3m)

  The 1,050 W sibling with 1.3 m input leads, for lower-power modules. It can serve the same project on its own strings, never mixed into an S1200 string.

• S1000 Power Optimizer (Short Input 0.1m)

  The short-input S1000, again for a separate string of its own on the same commercial inverter.