Skip to main content

Gelbox for Splicing Connectors

DLG-APPROVED: "Resistance to ammonia"

Download printable version

The Approval

A test mark “DLG-APPROVED for individual criteria” is awarded for agricultural products which have successfully fulfilled a scope-reduced usability testing conducted by DLG according to independent and recognised evaluation criteria. The test is intended to highlight particular innovations and key criteria of the test object. The test may contain criteria from the DLG test scope for overall tests, or focus on other value-determining characteristics and properties of the test subject. The minimum requirements, test conditions and procedures as well as the valuation bases of the test results will be specified in consultation with an expert group of DLG. They correspond to the recognized rules of technology, as well as scientific and agricultural knowledge and requirements. The successful testing is concluded with the publication of a test report, as well as the awarding of the test mark which is valid for five years from the date of awarding.

The DLG-APPROVED individual criteria test concerning the resistance of barn components to ammonia encompasses testing the resistance of splicing connectors and switch boxes to ammonia-laden barn air under laboratory conditions. This resistance is evaluated on the basis of visual and gravimetric characteristics as well as electrical parameters. DIN EN 60999-1 is used for orientation in this process. Other criteria were not investigated.

Assessment in brief

The Gelbox from WAGO GmbH & Co. KG has successfully completed the resistance to ammonia test. It can therefore be assumed that no accelerated ageing will occur during use in practice. No relevant differences were ascertained when the splicing connectors were tested electri­cally before and after the DLG chamber test. A significant increase in electrical resistance at the tested connection points was ruled out. None of the test samples revealed any anomalies during either the final visual inspection or the gravimetric analysis before and after the chamber test.
The test results are briefly ­summarised in Table 1.

Table 1: Summary of test results

Dlg Quality profile  Evaluation* 
Resistance to ammonia

*    The DLG test framework provides the following options in its evaluation schemes:    
■■■  or better = meets, exceeds or clearly exceeds the specified DLG standard
■■,  = meets the legal requirements for marketability,
 = failed

The product

Description and specifications

The WAGO Gelbox is a small, compact box that is filled with silicone-free gel. It is a tested and certified complete system consisting of Gelboxes and WAGO Splicing Connectors. The WAGO Gelbox offers WAGO Splicing Connectors protection against moisture in accordance with ­protection class IPX8. This therefore enables them to be permanently protected against moisture and the influence of ammonia.

Table 2 contains an overview of the most important characteristics of the gelbox.

Table 2: Technical data (according to manufacturer)

Gelbox for Splicing Connectors
Item number207-1331207-1332207-1333207-1431207-1432207-1433207-1372207-1373
Conductor cross-section range*up to 4 mm²0.5 to 6 mm³0.2 to 4 mm³
Housing materialPolypropylene
Gel materialPolyurethane
Voltage range*see connector voltage
Rated current*see connector current
Rated surge voltage2.5 kV
Insulation resistance5 MΩ
Physical propertiesIPX8

*    The conductor cross-section range, voltage range and rated current are dependent on the splicing connector that is used and
are specified in the respective data sheet. Further information in this regard can be found on the manufacturer’s website.

The Method

Ammonia resistance

The DLG-APPROVED individual criteria test concerning the resistance of barn components to ammonia was conducted as a laboratory test according to the DLG test standard for agricultural use. This laboratory test is intended to determine whether a product is suitable for withstanding the harmful effects of barn air over a period of 10 to 20 years.

To conduct the test, several gelboxes of different sizes were placed in the DLG test chamber together with multiple corresponding splicing connectors and were exposed to ammonia over a period of time. The test in the test chamber was conducted under the following climatic conditions:

Duration of the test 1500 h
Air temperature 70 °C
Relative humidity 70 %
Ammonia concentration 750 ppm

To evaluate their resistance to ammonia, the test samples were visually inspected and analysed gravimetrically and by measuring the voltage drop before and after the climate test. The gelbox/connector combinations that are regarded as particularly critical were used as test samples. The most critical combinations are those with the highest loads. This applies to the connections with the highest number of conductors and to the highest displaced volume in the gelboxes.

The voltage drop measurement was conducted on the basis of DIN EN 60999-1:2000, whereby three identical samples were tested for each critical combination. A total of 30 samples were subjected to a voltage drop test. A permanent current line was routed to each connection within a gelbox. Measurement leads routed in parallel enable a voltage drop measurement to be carried out at each connection. In deviation from the standard, loading with rated current for one hour beforehand was forgone. 1/10 of the specified rated current was selected as the test current. In accordance with the standard, each connection point may drop by a maximum of 15 mV. A maximum of 3.0 mV is therefore permissible with reference to the selected test current and the measurement via a connection.

The gelbox/connector combinations were additionally tested as separate test samples in order to ascertain gravimetric changes. An untested sample was also available as a reference sample for each test sample.

Detailed account of the test results

Ammonia resistance

The resistance of the materials to ammonia was investigated in the form of a laboratory test according to the DLG test standard for agricultural use.

Visual inspection

During the visual inspection, no relevant changes were ascertained after the climate test. The slight dis­colouration of the gel may be due to the increased temperature in the test chamber. Following the chamber test, both the gelboxes and the splicing connectors corresponded visually to the specifications for proper operation.

Gravimetric analysis

No anomalies were determined during the gravimetric analysis. The comparable differences before and after the climate test were < 1 %.

Voltage drop test

The requirements for the permissible voltage drop were adhered to in accordance with DIN EN 60999-1:2000. Less than 3 mV were measured at all of the tested connections both before and after the climate test. The average comparable change in voltage before and after the climate test was 6 % to 7 %.

Based on the available results, it can be assumed that the gelbox is resistant to ammonia in combination with the corresponding splicing connectors.


The WAGO Gelbox has passed the DLG-APPROVED individual criteria test concerning resistance to ammonia in the tested form. Based on this result, it can be assumed that the gelbox is resistant to ammonia-laden barn air in combination with the splicing connectors specified by the manufacturer and that no additional acceleration of the ageing that is normally to be expected occurs.

Manufacturer and applicant

WAGO GmbH & Co. KG
Hansastraße 27
32423 Minden

Phone +49 (571) 887-0


Test implementation

DLG TestService GmbH, Gross-Umstadt location
The tests are conducted on behalf of DLG e.V.


Division head
Dr. Ulrich Rubenschuh

DLG test framework
‘Resistance of barn components to ammonia’,
status 07/2023

Test engineer
Dipl.-Ing. (FH) Tommy Pfeifer *

*    Author


DLG TestService GmbH - Groß-Umstadt location • Max-Eyth-Weg 1 64823 Groß-Umstadt Germany • Tel.: +49(0)69 24 788-611 •