{"id":14737,"date":"2025-12-16T15:46:31","date_gmt":"2025-12-16T14:46:31","guid":{"rendered":"https:\/\/onload.reinhausen.com\/de\/?p=14737"},"modified":"2025-12-16T15:46:32","modified_gmt":"2025-12-16T14:46:32","slug":"mobile-resonance-testing-for-medium-voltage-cable","status":"publish","type":"post","link":"https:\/\/onload.reinhausen.com\/en\/12-2025\/mobile-resonance-testing-for-medium-voltage-cable\/","title":{"rendered":"Mobile tester for medium voltage"},"content":{"rendered":"\n
\n\n\n\n

A tiny grain of sand is enough to plunge an entire city into dark\u00adness. If even the small\u00adest par\u00adti\u00adcles of dirt get into the con\u00adnec\u00adtion sleeves when lay\u00ading pow\u00ader cables, a vio\u00adlent \ufb02ashover can occur under oper\u00adat\u00ading volt\u00adage. Not only do parts of the ener\u00adgy sup\u00adply sys\u00adtem col\u00adlapse, but cable sec\u00adtions and con\u00adnec\u00adtion sleeves are also destroyed and must be replaced. But how can this be pre\u00advent\u00aded? Defects in the insu\u00adla\u00adtion and con\u00adnec\u00adtion sleeves are not vis\u00adi\u00adble to the naked eye. Over the last three decades, the res\u00ado\u00adnance test\u00ading method has estab\u00adlished itself as a reli\u00adable and proven prin\u00adci\u00adple for inspect\u00ading cables for faults before com\u00admis\u00adsion\u00ading, but also dur\u00ading rou\u00adtine checks or after repairs.<\/p>\n\n\n\n

HIGHVOLT \ufb01rst devel\u00adoped a mobile sys\u00adtem for on-site test\u00ading back in the 1990s, there\u00adby estab\u00adlish\u00ading the method. The pro\u00adce\u00addure involves apply\u00ading a test volt\u00adage and, at the same time, per\u00adform\u00ading a par\u00adtial dis\u00adcharge mea\u00adsure\u00adment. This serves to detect dis\u00adcharges in the cable that could lead to a break\u00addown. In this way grid oper\u00ada\u00adtors can elim\u00adi\u00adnate faults before the cable is con\u00adnect\u00aded to the grid. Until now, the process has only been used at high and extra-high volt\u00adage lev\u00adels, but that is about to change. HIGHVOLT has devel\u00adoped a new mobile test\u00ading sys\u00adtem that is suit\u00adable for both medi\u00adum volt\u00adage and the low\u00ader high-volt\u00adage lev\u00adel. Michael Hensel, Senior Sales Engi\u00adneer at HIGHVOLT, explains: \u201cThe spe\u00adcial fea\u00adture of our sys\u00adtem is that it cov\u00aders a very wide range with a test volt\u00adage of up to 75 kilo\u00advolts.\u201d<\/p>\n\n\n\n

\n\n\n\n

Compact cable tester  <\/h4>\n\n\n\n

The res\u00ado\u00adnance test\u00ading sys\u00adtem for medi\u00adum-volt\u00adage cables is designed for a test volt\u00adage of up to 75,000 volts and fits on small\u00ader trucks and trail\u00aders. <\/p>\n\n\n\n

\n

Click on the <\/i>-sym\u00adbols for more infor\u00adma\u00adtion on the areas.<\/p>\n\n\n\n

\n\t\t\t\t\t\t
<\/div>\n\t\t\t\t\t\t
\n\t\t\t\t\t\t

The volt\u00adage divider<\/strong> mea\u00adsures and mon\u00adi\u00adtors the test volt\u00adage and is the con\u00adnec\u00adtion point to the cable.<\/p>\n\t\t\t\t\t\t <\/div>\n\t\t\t\t\t\t <\/div>\n\t\t\t\t\t\t <\/div><\/span><\/a>

\n\t\t\t\t\t\t
<\/div>\n\t\t\t\t\t\t
\n\t\t\t\t\t\t

The res\u00ado\u00adnance reac\u00adtor<\/strong> gen\u00ader\u00adates the test volt\u00adage for the cable.<\/p>\n\t\t\t\t\t\t <\/div>\n\t\t\t\t\t\t <\/div>\n\t\t\t\t\t\t <\/div><\/span><\/a>

\n\t\t\t\t\t\t
<\/div>\n\t\t\t\t\t\t
\n\t\t\t\t\t\t

The Con\u00adtrol and pow\u00ader sup\u00adply<\/strong> unit con\u00adsists of the fol\u00adlow\u00ading com\u00adpo\u00adnents: The fre\u00adquen\u00adcy con\u00advert\u00ader<\/strong> sets the desired test fre\u00adquen\u00adcy and ensures that the test volt\u00adage on the cable remains sta\u00adble. The exci\u00adta\u00adtion trans\u00adformer<\/strong> feeds the ener\u00adgy into the res\u00ado\u00adnance cir\u00adcuit, and the test sys\u00adtem can be con\u00adve\u00adnient\u00adly oper\u00adat\u00aded via a dis\u00adplay.<\/p>\n\t\t\t\t\t\t <\/div>\n\t\t\t\t\t\t <\/div>\n\t\t\t\t\t\t <\/div><\/span><\/a>

\n\t\t\t\t\t\t
<\/div>\n\t\t\t\t\t\t
\n\t\t\t\t\t\t

Par\u00adtial dis\u00adcharge (PD) mea\u00adsure\u00adment<\/strong> is used to mea\u00adsure tiny dis\u00adcharges in the insu\u00adla\u00adtion of cables and con\u00adnec\u00adtion sleeves that can lead to a flashover.<\/p>\n\t\t\t\t\t\t <\/div>\n\t\t\t\t\t\t <\/div>\n\t\t\t\t\t\t <\/div><\/span><\/a><\/div>\n<\/div><\/div>\n\n\n\n

Medium voltage under pressure<\/h2>\n\n\n\n

In medi\u00adum volt\u00adage, the so-called very low fre\u00adquen\u00adcy (VLF) test has been the stan\u00addard method for test\u00ading cables. As the name sug\u00adgests, these sys\u00adtems oper\u00adate with a very-low-fre\u00adquen\u00adcy alter\u00adnat\u00ading volt\u00adage of just 0.1 hertz. The advan\u00adtage is that this method does not require high test cur\u00adrents, which means that the test equip\u00adment can be small in size. But the method also has its pit\u00adfalls, as Hensel explains: \u201cFor test\u00ading, a test fre\u00adquen\u00adcy is used that does not cor\u00adre\u00adspond to real con\u00addi\u00adtions at all. Depend\u00ading on the coun\u00adtry, the mains fre\u00adquen\u00adcy is 50 or 60 hertz, so test\u00ading at 0.1 hertz means there is a risk that faults will not be detect\u00aded at all.\u201d<\/p>\n\n\n\n

\n
<\/div>\n\n\n\n
\n

\u201cA test\u00ading sys\u00adtem should be as close as pos\u00adsi\u00adble to the real oper\u00adat\u00ading con\u00addi\u00adtions in the grid.\u201d<\/p>\nMichael Hensel, Senior Sales Engi\u00adneer at HIGHVOLT<\/cite><\/blockquote>\n\n\n\n

<\/div>\n<\/div><\/div>\n\n\n\n

Since the insu\u00adlat\u00ading medi\u00adum behaves dif\u00adfer\u00adent\u00adly depend\u00ading on the fre\u00adquen\u00adcy, it is also pos\u00adsi\u00adble that prob\u00adlems may be indi\u00adcat\u00aded at a low fre\u00adquen\u00adcy that would nev\u00ader occur in nor\u00admal mains oper\u00ada\u00adtion. \u201cThere\u00adfore, a sys\u00adtem that comes as close as pos\u00adsi\u00adble to real con\u00addi\u00adtions is more suit\u00adable. Our test sys\u00adtems, which have been in use world\u00adwide in high and extra high-volt\u00adage appli\u00adca\u00adtions for 25 years, have proven that they are capa\u00adble of doing this,\u201d says Hensel. Reli\u00adable fault detec\u00adtion is also becom\u00ading increas\u00ading\u00adly impor\u00adtant in medi\u00adum volt\u00adage, in par\u00adtic\u00adu\u00adlar because the expan\u00adsion of renew\u00adable ener\u00adgies places heavy demands on medi\u00adum-volt\u00adage cables. How\u00adev\u00ader, the test sys\u00adtems that HIGHVOLT builds for high and extra-high-volt\u00adage are too large for these cas\u00ades, because medi\u00adum-volt\u00adage cables are usu\u00adal\u00adly locat\u00aded in places that are dif\u00adfi\u00adcult to access with a large truck.<\/p>\n\n\n\n

Small reactor, big performance<\/h2>\n\n\n\n

The engi\u00adneers at HIGHVOLT there\u00adfore redesigned the sys\u00adtem so that it does not exceed a total weight of 3.5 tons and can thus be trans\u00adport\u00aded by a small truck or trail\u00ader. The most impor\u00adtant lever for achiev\u00ading this is the res\u00ado\u00adnance reac\u00adtor, which pro\u00advides the test volt\u00adage. This is no easy task, as the reac\u00adtor must remain ther\u00admal\u00adly and mechan\u00adi\u00adcal\u00adly sta\u00adble through\u00adout the entire one-hour test process with\u00adout defor\u00adma\u00adtion or over\u00adheat\u00ading.<\/p>\n\n\n\n

\u201cWe have the exper\u00adtise to imple\u00adment such com\u00adpact designs\u2013not every\u00adone can do that,\u201d says Hensel. The reac\u00adtor that HIGHVOLT has designed for the sys\u00adtem is not only com\u00adpact but also \ufb02ashover-proof. This means that, unlike for larg\u00ader sys\u00adtems, no addi\u00adtion\u00adal pro\u00adtec\u00adtive mea\u00adsures are nec\u00ades\u00adsary. One cus\u00adtomer from the US and anoth\u00ader from Asia are already using the new test sys\u00adtem. \u201cSo far, we haven\u2019t had any feedback\u2013that\u2019s a good sign,\u201d smiles Hensel.<\/p>\n\n\n\n

<\/div>\n\n\n\n
\n
\n\n\n
\n
<\/figure>\n<\/div>\n\n\n

YOUR CONTACT<\/h2>\n\n\n\n

Do you have any ques\u00adtions about the medi\u00adum-volt\u00adage test sys\u00adtem?<\/strong>
Michael Hensel is here to help:
<\/i><\/a>M.Hensel@highvolt.com<\/a><\/p>\n<\/div><\/div>\n","protected":false},"excerpt":{"rendered":"

Rein\u00adhausen sub\u00adsidiary HIGHVOLT is now also estab\u00adlish\u00ading its res\u00ado\u00adnance test\u00ading method in the medi\u00adum-volt\u00adage range. This ensures greater secu\u00adri\u00adty in grid oper\u00ada\u00adtion.<\/p>\n","protected":false},"author":4,"featured_media":14738,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"wp_typography_post_enhancements_disabled":false,"footnotes":""},"categories":[45,1],"tags":[],"class_list":["post-14737","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-12-2025","category-onload"],"acf":[],"_links":{"self":[{"href":"https:\/\/onload.reinhausen.com\/en\/wp-json\/wp\/v2\/posts\/14737","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/onload.reinhausen.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/onload.reinhausen.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/onload.reinhausen.com\/en\/wp-json\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/onload.reinhausen.com\/en\/wp-json\/wp\/v2\/comments?post=14737"}],"version-history":[{"count":7,"href":"https:\/\/onload.reinhausen.com\/en\/wp-json\/wp\/v2\/posts\/14737\/revisions"}],"predecessor-version":[{"id":15734,"href":"https:\/\/onload.reinhausen.com\/en\/wp-json\/wp\/v2\/posts\/14737\/revisions\/15734"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/onload.reinhausen.com\/en\/wp-json\/wp\/v2\/media\/14738"}],"wp:attachment":[{"href":"https:\/\/onload.reinhausen.com\/en\/wp-json\/wp\/v2\/media?parent=14737"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/onload.reinhausen.com\/en\/wp-json\/wp\/v2\/categories?post=14737"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/onload.reinhausen.com\/en\/wp-json\/wp\/v2\/tags?post=14737"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}