Schaudt OVP 01


The Schaudt Elektroblock EBL range is often, incorrectly, singled out on the Forums as having a particular issue because, so it is alleged, they do not have Spike protection built in and this is why the charger units inside the boxes fail.  

The Schaudt Elektroblock range DOES have built in spike protection in the form of a Metal Oxide Varister (MOV). MOV is a  very effective way of trapping Spikes which is why it is used by almost all the Charger unit manufacturers from  Arsilicii to Nordelettronica. 

The confusion seems to have arisen because Schaudt manufacture an add on module called the Over Voltage Protector 01 which is sold by some as a Spike suppressor when it is not
What the OVP 01 does is cut all power to the protected device if the voltage goes outside preset limits ie, below 190v or above 265v.



The inbuilt Spike protection in almost all Schaudt charger units from a EBL 99 to a EBL 267 will protect against all but the most powerful Spikes. However, it is not very good at blocking slower rising voltages, for example when a generator becomes faulty and puts out a slowly rising voltage greater than 265v, or it's voltage drops below 190v. 

That is where the OVP 01 is designed to help, exactly as the Schaudt Technical document explains.  

                                                    

We have seen less than 0.01% of EBL failures down to mains borne Spikes and almost every one of those was in a Country where Thunder storms and Lightning strikes are more common than the UK : Italy, Southern France, Spain and Portugal. In almost all cases there was a lightning storm nearby and  the 240v Fridge,  Heating, TV, Laptop, etc were damaged at the same time as the Schaudt unit. 
In the Italian case we estimated over 600v had hit the Motorhome so it is not surprising their total bill was over £2,500 to replace the damaged elements. And yes they had an OVP 01 fitted but the EBL99 did not survive.
 
 
The best protection is to remove the mains Electric Hook Up lead from the motorhome if an electrical storm is withi a 10 mile vicinity, protect ALL the sensitive electronics in the MH, not just the charger unit.
Remember we are talking here about Hot countries prone to sudden electrical storms where the rural Electrical Infrastructure is not as effective at damping down high voltage strikes on power lines. Even then the risk is low.


Update August 2017 -

To provide a better service we embarked on a program of 'testing to destruction' some of the Schaudt 18amp chargers.
It has thrown up some interesting results.  
The testing has only been relatively limited, so some of the behaviour seen may not be representative under more thorough investigation, but the results indicate that the Schaudt charger when working hard, like charging poor batteries, can be susceptable to very specific mains anomalies. 
NOT the usual Voltage Spikes as had been previously suggested, but interruption of the supply creating internal waveform distortion. 

Such disruption to the waveform may occur when the power is cut then quickly re-established, like turning a mains 'Breaker' of and then on very quickly. 
It didn't always cause damage, but multiple mains supply 'breaks and reconnects' increased the risk of failure.  

Damage to the charger occured, yet the voltage never 'spiked' at all. It didn't rise above 235v, so this isn't about voltage spikes. 



We found that under these instances an OVP01 gave significant 'accidental' protection, by cutting Waveform distortion, thereby protecting the EBL charger.

Where the mains supply is broken and then quickly re-established, an OVP 01 detected the falling voltage and disconnected the mains 230v supply to the charger. 
The OVP then waits for 1.5 seconds, and only if the mains is then back in tolerance, does it re-connect the Schaudt charger to the 230v supply, by which time the charger has shut down and goes through a normal start up.
This prevents disruption to the waveform in the Charger circuitry.  

This type of mains supply disruption will not impact any other 230v appliances in the Motorhome, just this type of Inverter charger.


Note that we were only able to 'destroy' the charger during testing when it was working really hard, typically on poor batteries or an overlarge battery bank. 
In other words, a poor battery increases the likelyhood of this type of mains anomaly inflicting damage on the charger.  
So yet more potential impact on a charger by poor batteries.

What was also interesting, was that the damage occurred irrespective of the rating of the components. Even the higher rated ones succumbed.


So contrary to what we have stated before, we now believe the OVP 01 is a significant asset to a Motorhome/Caravan, but not for reasons of Spike protection as stated on the Forums. 

We therefore now advise the fitment of an OVP 01 to all Schaudt Elecktroblocks with the 18amp charger.
The older Elektroblock EBL 99 with the 16amp chargers (usually pre 2004) are a very different design and may not be affected by the above mains anomaly. Due to their age we have no plans to carry out the same testing on the 16amp chargers. 

We still don't believe the OVP 01 will trap damaging mains Spikes, it was too slow acting in the tests we used.
Fitting a  secondary Spike/Surge protector, in addition to an OVP 01, is a cheap option where the extra protection might protect the OVP 01 itself.  Especially if  the Surge protector also has an isolation switch.


Something like the above power adapter/Surge protector at under £4 is suitable as each outlet has it's own 'Neon' lit switch. 
As well as affording extra protection to an OVP 01/EBL, the switch allows easy isolation from the mains, for example before starting up/shutting down a generator, or when you suspect some electrical work is being done on site, etc. 
The 'telltale' mains connected red light in the switch itself is also a useful diagnostics aid in determining if 230v is coming into the vehicle. 


They can be found on eBay under "3 Way 13A Switched Surge Protected adaptor UK Mains Plug-in With Neon" at £3.90 including shipping.  
We have not bought from this seller, so are not able to recommend them, but there are plenty of similar sellers on eBay.
 


Note the above text has been written by myself (Natalie) following conversations with Martin the Senior Technician and may not be a totally accurate 'technical' translation of what was said. But is probably a better 'laymans' translation?



We have no plans to sell or stock the Schaudt OVP01, to maintain impartiality on products we recommend, but it can be purchased from Brownhills who frequently advertise on eBay.



We don't sell batteries, but we have created a web page with lots of information to help you choose the best ones from the cheapest suppliers, seebattery-technology.php



The reason we say the OVP 01 has an 'accidental' benefit in protecting an EBL charger from the above type of mains anomaly is because no mention is made of this in the Schaudt OVP 01 manual, which talks only of Overvoltage protection, it states :

In recent years there has been an increasing number of faults caused by overvoltage in devices
operating on mains power in motorhomes and caravans.
In a motorhome almost all consumers are now supplied via the 12V onboard power supply.
Typical 230V devices are usually the 12V charging system (Electroblock) and the refrigerator.
In 12V charging systems the charging module is affected by the overvoltage.
This is particularly problematic as then neither mains operation nor battery charging is possible.
The typical causes of mains overvoltage are:
• lightning strikes into the public power supply
• generator operation (overshooting of the voltage during start-up in small emergency power
generators or on ferries)
• poor electric installations on camping sites, particularly in Southern Europe, where long, often retrofitted cables and poorly contacted neutral wires lead to overvoltage
by shifting the neutral point.
Although our devices are robust and operate smoothly for hours in tests at 300V, they can
occasionally fail due to overvoltage.
For this reason Schaudt GmbH has developed the overvoltage protection ovp01.


As can be seen there is no consideration in the design for any other type of mains issue, except overvoltage. 


The EBL itself will protect itself  from any true Voltage spikes, so long as they are not major ones. 
A Spike/Surge protecting MOV can be seen across the 230v input supply in the below photo of a Schaudt Elektroblock EBL99 charger PCB, just after the Fuse :