• I have bought Rolls again, 1 off Rolls S12 27 (105Ah @ 20Hr) this time direct from Barden UK.

    A major factor in choice is weight. I only want to lift around 30Kg. The previous HT 31 was 27.5Kg. The new S12 27 weighs 24.5 Kg, one size down from the HT/S12 31.

    Details for S12 27

    Rolls S12 27 – 12V Series 4000 Battery < £154: 3 Years Warranty

    Physical Specifications

    Weight: 24.5 kg ~ 54lbs | Length 32.1 cm 12.63" | Width 17.1 cm 6.75" | Height Inc. Term. 23.8 cm 9.38"
    Volts: 6 | BCI: Grp 27 | Cells: 6| Plates/Cell: ?
    Terminal Type DT
    Included Hardware S/S Hex Cap Screw, Nut, Lock & Flat Washer
    Size & Thread 5/16″-18 x 1-1/2″

    Electrical Specifications
    Cold Crank Amps (CCA) 0°F / -17°C 660 Marine Crank Amps (MCA) 32°F / 0°C 825 Reserve Capacity (RC @ 25A) 185 Minutes Reserve Capacity (RC @ 75A) 53 Minutes

    Charge Voltage Range
    Bulk : Absorption = 2.45-2.5 V/cell @ 25°C (77°F) or 14.7v to 15v
    Float Voltage = 2.25 V/cell @ 25°C (77°F) or 13.5v
    Equalisation = 15.48 to 16.02 SG 1.280

    Recommended Charge Current Capacity (String) 15A
    Maximum Charge Current (String) 25 A
    Self-Discharge Rate 5%-10% per month at 25°C (77°F)

    Hour Rate Capacity : AMP Hour : Current / AMPs
    @ 100 Hour Rate 140 AH 1.4 A |@ 20 Hour Rate 105 AH 5.25 A | @ 15 Hour Rate 99 AH 6.58 A
    @ 10 Hour Rate 89 AH 8.93 A | @ 8 Hour Rate 87 AH 10.89 A | @ 5 Hour Rate 85AH 17.01 A | @ 1 Hour Rate 38 AH 37.8 A

    Amphere hour capacity ratings based on specific gravity of 1.280.
    Reduce capacities 5% for specific gravity of 1.265 and 10% for 1.250.

  • 7th April. Just attached the cables to the roof of the workshop by first fixing an upright to one of the purlins and then a batten from that to one of the rails. The attachement to the rails is just ~ wedged under. The wood is Siberian Larch left over from the rafters and battens respectively.

    The batten had a copper strip running on it's upper edge and the cables are held to the upper face by fabricated copper clamps. The clamps are made from flattened 10mm copper pipe comming out as some 50mm long and 15mm wide and 2mm thich. They are bent to shape and fastened wiyth two stainless screws. The copper strip is fastened with bronze ringed nails.

    fixing power cable from pv panels via batten.

    9th April. Fitted copper earthing strip to wall of workshop. Still have to connect a) the frames of the pannels together b) the panels frames to the earth conductor c) joint parts of the copper earth conductor and d) insert copper rod to earth and connect that to the joined up a,b and c.

    The cables are fastened with homemade clamps

    view of cables and earth strip fitted.

    The copper strip has been hammered into the chamfers which hopefully will allow for any expansion of timbers.

    10th April. Used s-old-id fuse box for 110v input from solar array. .

    8 amp twp way stormproof fuse box used for pv array 110 voltage input cables.

  • This is some 10 to 16 years old. Model 651.626.
    Brought it out as moved the Victron 1200 to the workshop and want soemthing to recharge the Fridge, Bag of Riddim II, Old Nokia 6303, and more.
    It seems fine though a bit noisey with the fan running even on low loads. It's desugned for 10 to 16 volts

  • Hi

    I have just bought an inverter form Wind and Sun UK, I called them for two reasons

    1) to find out what current the inverter takes when it is switched off and

    2) to say the manual was disappointing


    1) how does switching work as it isn't a power switch that physically breaks and joins the 200A input cables,

    i) What is the rating of the dc input cables?

    ii) How are the input DC cables connected, I imagine there must be some loss?

    iii) Does the power switch, in the off position, just a break in power to a relay, that when on enables the dc circuit to work and connects the DC input.

    2) The manual says very little, maybe there is little to say, but it could state

    i) the load in the off, as above,

    ii) the image in the index is very poor and hardly usable and the one on your website, which isn't mentioned in the manual isn't much better. Could you send me a detailed image or is their one on the website. All I could find is a version of the manual; which I made a screen shot of and enlarged.

    A third matter


    i) The UK 230v socket is upside down and the mains cable blocks easy access to the power switch.
    inverter socket2

    ii)Your image show it the correct way.
    Can I unscrew the body and correct this?

    iii) plus the socket isn't screwed in place and moves around a bit

    4. Finally I am disappointed it is made in China, prior to purchase I though it would be India like the MPPT 75|15

    Thank you

    Roger Lovejoy


    Cc Wind and Sun

    Roger Lovejoy

  • Cable or Wire: The tendency is to think of cable as large diameter and wire as small, but there is no definition.

    Here I'll use Cables for Electrics and Wire for Electronics. Although I intend to use the term cable, in using or refering to third party data cable may not be their preffered term. Further the term 'wiring' is used predominantly when installing electric power cables for buildings etc.

    The beginings of elctrical power system is the power source which, presently, in this case are three 250w photovoltaic panels connected in series giving around 110v with a max current of 9 amps. The array of panels is connected to an MPPT control unit by standard PV1-F 4 cabling that can carry 55 amps up to 60°C in open air.

    For more detail on PV1-F cables and temperture co-efficents see.
    Eland Data Sheet

  • Have extended the cooper strip to a piece of copper pipe some 4 to 5 feet of which is burried in a shallow channel that is used for rain overflow, to help conduction. The copper strip can be seen @ https://unveiled.info/solect/cables-from-panels; the PV frames need to be connected to the top strip along the roof batten

    May 4th Finished, a bit roughly, joining the copper strip parts together and the strip to the ground pipe.

    ground pipe joint
    ground pipe to copper conductor
    copper conductor lower joint
    copper conductor upper joint
    grounding pipe