Generators

Generators


Generators have normally been the preserve of the more affluent off roader, camper, or expedition users, and were generally very expensive to buy, thirsty, very heavy, bulky and cumbersome, and had relatively small power outputs for their size. In recent years the modern materials and manufacturing techniques now developed have seen reasonably priced, lightweight, fuel efficient, and powerful units to come within the scope of more potential users and customers. Many of these generators are made in the far east and many cheap units have entered the marketplace and most are to be avoided; but why, as with anything else today they often make outlandish claims about their products, which, when subjected to scrutiny, don’t stand up.

Confusion often reigns when people look at the marketing blurb which is designed to lure people into buying a specific type or model of generator, often this marketing blurb is very carefully worded to avoid legal repercussions against manufacturers and the model doesn’t deliver what it claims. Before selecting any generator ALWAYS READ THE SPECIFICATIONS for the generator as this reveals the true figures for many things.

Generators classify their output in one of several ways, smaller units may use Watts or Kilowatts while others may use a KVA (kilovolt amps) rating, and some may use Amps at a specific voltage to rate their output; and these ratings need to be taken with a pinch of salt.
Generators normally have two ratings for their output, one is the maximum output which is the theoretical maximum output a unit may provide; while the second is the continuous maximum rating a unit may provide, and is always less than the maximum output. Continuous load is often called the “rated load” instead. So why two ratings? Many electrical items draw more electrical current when they start up, this then drops to a lower current consumption when the electrical item is running, and is the reason many generators have two ratings. Always ignore the maximum output rating and focus on the continuous rating or rated load as this is the true power the unit will provide, and on many cheaper units the difference between the maximum output and the continuous output is massive, often the continuous output or rated load is as little as half the maximum claimed output.
Many generators in the UK will have two output voltages, some will have only one voltage output for AC power, some will be 240 volts, some will be 230 volts, and some will be either 240 or 230 volts and 110 volts. One important question to ask is “do I need 110 volts” and if the answer to the question is no, then why pay extra for it; and whether the unit is a single or dual voltage output you need to ensure this output voltage is a regulated output, but why? Regulated output means the output voltage from the unit is stable at its working voltage and if you measure it with a multimeter it will remain stable irrespective of what you run off the generator as long as its continuous rating is not exceeded. Many cheaper units are not regulated which means the output voltage can vary wildly, unregulated units will only supply the correct voltage when the item connected to it is rated at its continuous rated output, if the item being run is lower than this the voltage will rise well above 240 volts. Obviously this will damage most appliances if their rated voltage is exceeded; in testing we did we actually saw unregulated voltages rise to above 300 volts, and some above 350 volts, this is unacceptable.
Many people run many electronic items off a generator and this can be very risky with many generators, always check the specifications to ensure the generator is “electronics safe”, many quality brands are, and cheap brands certainly are not. Electronics safe units have additional circuitry to avoid various issues such as spurious harmonics, voltage spikes, or current spikes which may damage sensitive electronic items such as laptop computers, sat nav’s, televisions, and many of today’s electronics which are in most things.

Many generators offer a DC power output, often this is 12 volts for battery charging, running portable equipment on 12 volts, or even engine starting equipment; once again ensure this is a regulated 12 volts output and is electronics safe. If this is tested with a multimeter the output voltage shouldn’t rise above 14.6 volts; in testing we have undertaken we have regularly seen unregulated units supply DC voltage in the mid 20 volt range, some have exceeded 30 volts. Imagine connecting that to your vehicle battery/ battery packs to charge them out in the field, your batteries would be fried in no time and the electrolyte would have been boiled away, and yes, unfortunately I have seen it happen, and too many times. Regulated DC (12 volts) voltages output current will also rise and fall in demand with the load placed upon it, if you charge your battery packs while out in the field the current will remain at its maximum, when the battery/battery pack is nearly charged its current will fall to prevent overcharging.

Generators with regulated, electronic safe 12 volt outputs can be used to replace a vehicle battery or separate battery pack to power most equipment around a camp, instead of using a battery pack as long as their maximum current output is not exceeded.

Noise is often an issue with many generators, and many campsites now place restrictions on generators such as where they can be run, and what hours they can be run between, and what hours they cannot be run between. Generators have become much quieter and they always have their noise output in DB (decibels) quoted, and often with a distance in metres, so what does this mean in reality.
One typical noise output may read 65DB @ 15M.
In reality this means that the noise level it will reach is 65 decibels if you are 15 metres away from the generator in open country, and there’s no obstruction between the generator and the sound measuring equipment, but on a campsite your neighbour may be only 5 metres away in a tent. He will be like a bear with a sore head if you run your generator all night and keep him awake, you may find if you run it for a second night that it may disappear altogether.

Understanding how noise is determined is crucial as you can select a low noise unit which is measured close to the generator, one example is a current generator which produces 52DB at 7M, and basically the noise is 52 decibels maximum at 7 metres from the unit. This is preferable, and much quieter than the above example, especially if part of your trip means staying on local commercial camp sites with others in close proximity.

Fuel consumption is vital to successfully running a generator as you need to ensure you have enough fuel for a trip. Many generators rate their fuel consumption differently to make them appear more fuel efficient, a reputable brand may rate their fuel consumption at 2L/Hr at rated load, and basically this means the unit will consume 2 litres of fuel per hour if it’s working at its rated or maximum continuous output. Many other less reputable brands may only rate their units at 1.5L/Hr at ½ rated load, or even at ¼ rated load, but why? Many measure their fuel consumption at the generator engines most efficient working load and often this may be at only ½ or ¼ of its rated load; if you run the unit at its full rated load its fuel consumption may rise disproportionately to that of its competitors at its full rated load.
Never buy a generator if it does not give its fuel consumption at rated load as you won’t know how much fuel you need to carry, often you may have to make an additional fuel trip to fetch more fuel as you will run out because your generator is a gas guzzler compared to its competitors.

Many generators will give the size of its fuel tank, this is used along with its fuel consumption figures to determine how long the unit will run on a tank of fuel, if the unit consumes 2 litres of fuel at its rated load, and it’s got an 8 litre fuel tank you know you have a minimum of 4 hours running time.

Weight is a major issue for expedition or camping and many people find newer generators do not weigh anything like older units, low weight combined with compact dimensions makes them easy to transport and store in a vehicle, and all manufacturers will state the weight of a specific model.

Many generators have a range of additional features, many are useful, others are gimmicks, and some of the useful features are:

Circuit breakers or RCD protection – these automatically disconnect the equipment from the generator by opening or tripping the breaker if the electrical equipment its running becomes defective or an electrical cable becomes damaged.

Low Oil Alert – this can be either a visual or audible alert if the engines oil becomes low, often better units have both visual and audible alerts to warn a user of impending damage from low engine oil.

Automatic Low Oil shutdown – if the engine runs low on oil it will automatically shut the engine off and not allow it to start until the engine oil is replenished, this is a useful feature to those leaving a camp site with a generator running, possibly to recharge a battery pack.

Cheap two stroke or more expensive four stroke unit????????

Cheap two stroke generators are just that, cheap and nasty, and will not survive any arduous off road trip, they are of poor quality, and have poor outputs and very high levels of exhaust emissions.
Reputable brands are of much better quality than cheaper brands and have much better durability and power outputs, and many current ones have oil injection systems to reduce exhaust emissions.

Two stroke generators are lighter than four stroke units, much noisier, all have to have oil and petrol carried, and many countries with stringent emissions levels, two stroke engines are banned under environmental emissions regulations.

Four stroke units are heavier than two strokes, much cleaner on exhaust emissions, not banned in any country with stringent environmental conditions, and considerably quieter; and you only have to carry petrol to power them.

Assassin

Something as simple as baffle boards are a great addition, it's amazing how quiter they can be with the noise deflected upwards.

Tom Mc wrote:

Something as simple as baffle boards are a great addition, it's amazing how quiter they can be with the noise deflected upwards.

Even quieter if you leave them at home........ nasty horrible things

I removed my generator, given that it had run for jst over 200 hours in 19 years , previous owners had also thought so given that it spent years on expedition.

What about diesel generators? I know they tend to be noisier and heavier and certainly more expensive but I want a vehicle that only use ones fuel if possible for everything.

Mind you I have had a so called silent running small Honda generator for about 8 years and I doubt if it has runn for more than about 2 hours in total.

Robin

what do you need a generator for ?

mine was to power aircon - so i took the aircon off too

We have a geni, useted to power caravan when no electic hook up available, SWMBO does not do cold so run fire at nigh also heat the water, then run genie through the day to top up battrey, at LR shows 1 gal used to last weekend friday to monday,

Depends what you're up to. For Yoda it makes sense at shows, as he says, "SWMBO does not do cold".

In a dedicated camper like the Iveco, that another matter. Journeys around the UK no, but I wouldn't have though a small genny on a long-distance expedition was such a bad thing to have - providing it gave enough power to do a spot of emergency welding for instance (no pun intended). I realise expeditions aren't races so far less chance of breakages, but you never know what's around the next corner. The peace of mind a genny would give has to be worth the additional weight/space ... wouldn't it?

Still not convinced. My other half doesn't do cold either so the truck has a webasto. Like i said my gennie had done 200 hours in nearly 20 years.

I run solar panels to top up batteries and keep the fridge going and all the lighting is LED. The fridge is an 80 litre compressor jobbie

I think for expedition use you have to need to gennie otherwise its another piece of kit you will be taking in and out and never use

I'm sure my truck sighed with relief when the gennie and tank were removed and nearly 150kgs dropped off the truck. I'd rather have a lighter truck - less risk of breaking stuff

I can see points for them , maybe i've been subjected to too many inconsiderate people with them and its done my head in. Drive to beautifull place (Don't inclde 4x4 shows in that !) and then make it all noisy with generator. Not for me

iveco4x4
I do agree with some of your thoughts, with the caravan we were able to keep geni in the D3.
But know we are going to do the Snow Leopard trip and get a camper van/truck, I dont think it will be coming with us, may a webasto, not sure about solar panels some say good some say not good.
And yes when we used CL site's only 5 vans, did not tend to use it then, used gas.

A bit of topic!! Also are parts for iveco engins good to get when going futher afield, like Russia China?

regards yoda

Onboard diesel generators are available and some of the newer inbuilt ones are very quiet as they have the benefit of being ultra baffled in the exhausts and confined to an accoustic chamber, much like the advancements in marine generator technologies, so are better for those running them for longer periods.

Some are even available purely as 12V units with integral invertor battery charging technologies, no 240V is supplied by these and their intelligent technologies mean they only fire up to charge the vehicle batteries as and when they are required, usually at a pre-determined voltage from the battery, which has a seperate monitoring circuit.