Made in the Germany, Lorentz S1-200 pumps are extremely robust
and designed to run from just 1 solar panel.
Generally for the UK it is suggested that 400Wp (or more) of panels is used. There is no problem with adding more power, it is only the 55V maximum on the pump controller that must mot be exceeded. So to help ensure power if you wanted to use 2 x large wattage modules in parallel then you could.
If you have limited sun, you may consider the S1-200 HR14 rather than the S1-200 HR23 as it will perform better when there is limited sun. The reason being that the starting power of the S1-200 HR23 is higher than the S1-200 HR14.
Self install, solar powered water pumps for drinking water, livestock or irrigation
Robust and reliable for permanent installation, but also easy to transport and move
Energy, cost and carbon saving giving you independence from the grid
There are three pump variants that cover the range of head and flows.
HR-23 Max. flow rate 3 m³/h Max. head 17 m [55 ft]
HR-14 Max. flow rate 1.9 m³/h Max. head 30 m [100 ft] - THIS LISTING
HR-07 Max. flow rate 1 m³/h Max. head 40 m [130 ft]
Data provided is the annual daily average based on using a single 375 Wp PV module at location 15N 0E.
If you have a borehole cover (or similar) with a set hole cutout to put in the motor cable, the Outside Diameter of the motor connector is 30mm, as long as the connector goes through the hole it can then be sealed by using a "split gland", splitable gland / divisible gland. These are split to go around the cable and allow you to install without removing the plug. If the hole is not big enough (25mm) then cut a bigger hole (32mm) and install a split gland.