A few weeks ago, after a long period of not being used, my girlfriend's car refused to start: the battery was flat.
A quick trip to Argos saw us equipped with the MCH6A battery charger for £29.99. This is one of the lower powered battery chargers on the market, but as she has a tiny car, we reasoned that a more powerful, more expensive charger would not be required.
The blurb on the box promised to charge her car's battery from flat to full within 14 hours.
First impressions of the unit were very positive. The charger has a carrying handle built into the case (useful, as although it is small, it is quite heavy), a six foot power lead and two four foot, colour coded charging leads.
The front of the charger shows a series of coloured LED's for 'Full charge', "Charging", "Power", and "Reverse polarity" (more of the last one later).
This small unit is recommended for lead-acid batteries of between 20 and 70Ah capacity.
We disconnected the battery leads on the car (important before charging), and inspected the battery cells. Two of them had low fluid levels so they were topped up to the full mark with distilled water. I 'borrowed' some from work, but it's available from stores like Halfords. Using tap water is not recommended as it can damage the cells.
With the battery checked and topped up, we then connected the charger leads to the battery terminals.
Here, we encountered two problems: one of design, the other of my own making.
Placing the charger on the floor, the leads were only just long enough to reach the battery terminals, with less than an inch to spare. A taller car, or one with the battery placed further from the edge of the car would have needed a support for the charger to sit on, closer to the battery; not a good idea.
Despite their short length, the leads are well designed, with an excellent grip for good electrical contact. The ends were also curved so that they could grip around the battery terminals.
Switching the power on resulted in, not the expected green 'Power' LED illuminating, but the orange 'Reverse polarity' light coming on. This was not right. A quick check revealed that I'd connected the charger leads the wrong way round to the battery terminals! Oops.
Fortunately, the charger is fitted with 'reverse polarity' protection, in case idiots (like me!) fit the leads the wrong way round, so no damage was done.
Once I'd connected the charger correctly, the green 'Power' and yellow 'Charging' LEDs lit, and the charger started to do its work.
Charging a lead acid battery can result in the production of explosive hydrogen gas. To prevent any build up of gas, we left the car bonnet fully up, with the car outside. Luckily it was a nice day, so we did not have to worry about rain (it is recommended to use the charger indoors in a well ventilated area).
Around eight hours later, the green 'Full charge' light was lit, indicating that the charging process had been completed (once fully charged, the MCH6A goes into 'maintenance' mode, so the battery will not be over charged).
This was much less than the 14 hours promised, but I assume that this was because the battery had not been completely discharged.
All that we needed to do now was to disconnect the power, disconnect the charger leads, and reconnect the battery to the car.
The car roared into life, showing that the MCH6A had done its job. I felt that my £29.99 was money well spent, on a well specified, compact little charging unit. If you have a small car, and need a charger, then this could be for you. The same manufacturer makes a range of more powerful chargers, for larger cars too.