Frequently asked questions
Here you will find some common questions and the appropriate explanations about our product range. If you have any further questions, please do not hesitate to contact us.
Assembly aid & instructions
[PDF 5,2 mb]For free-standing units, we recommend foundations made of concrete (B25), with a dimension of 450 x 450 mm per side of the frame. For smaller units, a continuous foundation with the following dimensions is required: system width + 450 x 450 mm. Depending on the soil conditions, the foundation must be enlarged. The foundation depth should be at least 700 mm, depending on the frost line in the ground. Before excavation, it is advisable to obtain a division plan from the responsible office about the planned installation site so that pipelines, electric cables, etc. are not damaged.
Please ensure that the cables are pulled in before concreting.
If the system is concreted into a concrete foundation, the inlet depth for the stand elements should be 350 mm - 500 mm.
If the system is screwed onto a concrete foundation, bolt anchors (diameter 10 - 12 mm) or equivalent must be used.
For finishing the screw connection or the transition into the ground, we recommend our covering rosettes.
When mounting letterbox systems on house walls, the corresponding recommendations of the roof manufacturers must be observed depending on the wall composition. Furthermore, it must be ensured that no cold bridges are created by the fastening screws. If necessary, use special dowels for wall insulation. For the calculation of the total weight of the systems, please refer to our weight specifications in the detailed information.
1. Check
The wall to which the letterbox system is to be attached must be clean and level. Make sure that the wall has the appropriate load-bearing capacity. A letterbox weighs between 5 and 18kg, depending on its size.
2. Measuring
Measure the mounting holes on the back of the unit. Transfer these measurements to the wall. Please observe the mounting height prescribed by DIN 13724. The centre line of the lowest insertion opening should not be less than 700 mm. The centre line of the top insertion opening should not be higher than 1,700 mm. Only in exceptional cases (accessibility) is the lower limit 400 mm and the upper limit 1,800 mm permissible.
3. Drilling
Drill holes in the wall and insert dowels into the holes. Attention: Hole sizes and types of screws depend on the respective wall condition and must therefore be determined by the customer. If in doubt, please seek expert advice on site.
4. Screwing
Open the doors of the boxes in which the fixing holes are located and insert the appropriate screws with the spacers into the holes. Screw the system together. This step is best carried out by three people.
Our flush-mounted systems are equipped with pre-punched cable inlets on all sides, which can be removed very easily if necessary. We recommend that the installation of flush-mounted systems be carried out by a master craftsman, as cold bridges can occur when systems are installed in house walls if the insulation layer is interrupted during installation.
1. Measure height and width
Take the exact width and height from the back of the letterbox. This is important because you need the dimensions without the plaster cover frame. Add approx. 20 mm to these dimensions in both height and width and then draw a rectangle with these dimensions on the wall where the system is to be installed. Please observe the mounting height prescribed by DIN EN 13724. The centre line of the lowest slot should not be less than 700 mm, and the centre line of the top slot should not be higher than 1,700 mm. Only in exceptional cases is the lower limit 400 mm and the upper limit 1,800 mm permissible.
2. Measure the depth
Now measure the total depth of the letterbox system, add 5 to max. 10 mm here.
3. Break out the niche
Then break out a niche from the wall within the marked rectangle and at the depth of the plant.
4. Fit in the plant
Then carefully fit the plant into this niche and, if necessary, correct the niche size.
5. Drilling
Position the unit in the final position and mark the drill holes on the wall. Remove the unit from the niche and drill the corresponding holes in the niche wall and insert the dowels into the holes. Caution: Hole sizes and types of grommets depend on the respective wall properties and must therefore be determined by the customer. If in doubt, please seek expert advice on site.
Tip: The system can also be attached via the side walls.
6. Screw down
Now insert the unit into the niche again, open the doors of the boxes in which the fixing holes are located and insert the appropriate screws through these boxes into the dowels. Screw the system together. Make sure that the plaster cover frame completely covers the niche.
In order to achieve optimum water protection for your mail, the system/mailbox should be equipped with projecting cladding or a rain cover, and if possible the mailbox or mailbox system should be located under a canopy. Mail is only protected from water if it is completely deposited in the box and the access flap is closed. Mail that is not fully inserted allows moisture and dirt to penetrate the letterbox. It is therefore necessary to plan sufficiently dimensioned letterboxes for the upcoming demand. We offer extra letterbox depths for increased mail volumes, and we are also happy to manufacture customised sizes. In certain extreme weather conditions, water can still enter (according to DIN EN 13724 up to 1ccm). This is not a reason for complaint.
Installation direction
In a letterbox system, the mail is protected from wind and weather. However, when installing a free-standing system, make sure that the front of the box does not face directly towards the weather side.
Our complete sets are usually ready for connection! We already carry out the programming for complete sets in our factory.
However, we always recommend having the electrical installation carried out by an electrician. Please always refer to the manufacturer's operating instructions for wallboxes, intercom systems and video systems!
Camera, intercom or wallbox preparation
We offer the preparation of cameras, intercoms and wallboxes from various manufacturers for our systems. The preparation does not include any end devices, it is the provision of the screw mounts, drill holes & holes. So that you can mount your end unit without any problems.
General warnings
Our light and bell modules as well as our light and bell push-buttons may be operated with a maximum of 12-24 volts! A transformer with a VDE mark must be used! A higher voltage can endanger human life and lead to the cancellation of the warranty. Only components with 100 % permissible duty cycle may be connected to the push-buttons and modules! Failure to observe this warning may result in: - Fire hazard - Personal injury - Destruction of components Installation and assembly of electrical equipment may only be carried out by a qualified electrician! Please check whether the power consumption of the standard mains unit is sufficient for your planned consumption (e.g. for bell, intercom, light control as well as cable length and cross-section).
Light push-button/bell push-button DR29 for designers
Light pushbuttons/bell pushbuttons as individual pushbuttons are used to switch on the lighting in the entrance area and/or a staircase or to activate a signal transmitter. They may only be connected to extra-low voltage (12 V DC).
Light pushbutton/bell pushbutton Grothe Protact
Light pushbuttons/bell pushbuttons as individual pushbuttons are used to switch on the lighting in the entrance area and/or a staircase or to activate a signal transmitter. They may only be connected to extra-low voltage (max. 24 V AC/DC, 1.5 A).
LED light
If our LED luminaires have not been completely prewired and connected by us, please note that they may only be operated at 12 V DC. Other voltages will destroy and shorten the life of the LED luminaire.
Caution: Always ensure correct polarity with DC voltage.
If your letterbox is in its original packaging, your keys will be in the letterbox (removed via the flap) or in the enclosed bag (which also contains the assembly aid and other small parts).
Every letterbox that leaves our premises is carefully checked and packaged. A declaration of care is enclosed by the employee who manufactured your new product. Should you still not be able to find your key, please do not hesitate to contact us.