A window drive is only as reliable as its supply cable. If the cable is too thin or too long, too little voltage reaches the drive. It then moves slowly, does not close fully or stops. This mainly affects 24 V drives, because at low voltage even small losses matter.<\/p>\n\n\n\n
In brief:<\/strong> At 24 V, current draw and cable length determine the cross-section. Calculate the voltage drop and if in doubt choose the next larger cross-section. Connect the drive\u2019s supply cable in a junction box with strain relief.<\/p>\n\n\n\n For copper cables, as an approximation: voltage drop in volts = 2 \u00d7 length in m \u00d7 current in A \u00f7 (56 \u00d7 cross-section in mm\u00b2). The length is the one-way distance from controller to drive; the factor 2 accounts for the outgoing and return conductor.<\/p>\n\n\n\n Example: a 24 V drive drawing 1 A, 20 m away, 1.5 mm\u00b2 cable. Voltage drop = 2 \u00d7 20 \u00d7 1 \u00f7 (56 \u00d7 1.5) \u2248 0.48 V, i.e. about 2%. That is not critical. With several drives on one cable, the currents add up.<\/p>\n\n\n\n The basics are explained in the glossary entry Cable cross-section<\/a>. How large the power supply must be is shown in the guide Calculate 24 V power supply<\/a>.<\/p>\n\n\n\n For short distances and one drive, 1.5 mm\u00b2 is often sufficient. For long cables or several drives, calculate the voltage drop and choose 2.5 mm\u00b2 or more if necessary.<\/p>\n\n\n\n Whether shortening is permitted is stated in the drive\u2019s instructions. If in doubt, do not shorten it but neatly place the excess length in the junction box.<\/p>","protected":false},"excerpt":{"rendered":" Laying cables for 24 V and 230 V window drives correctly: which cross-section for which length, calculating voltage drop, junction box, strain relief and typical mistakes.<\/p>","protected":false},"author":9,"featured_media":0,"comment_status":"open","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[1960],"tags":[],"class_list":["post-17860","post","type-post","status-publish","format-standard","hentry","category-planung-montage"],"acf":[],"_links":{"self":[{"href":"https:\/\/ventsystems.de\/en\/wp-json\/wp\/v2\/posts\/17860","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ventsystems.de\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ventsystems.de\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ventsystems.de\/en\/wp-json\/wp\/v2\/users\/9"}],"replies":[{"embeddable":true,"href":"https:\/\/ventsystems.de\/en\/wp-json\/wp\/v2\/comments?post=17860"}],"version-history":[{"count":0,"href":"https:\/\/ventsystems.de\/en\/wp-json\/wp\/v2\/posts\/17860\/revisions"}],"wp:attachment":[{"href":"https:\/\/ventsystems.de\/en\/wp-json\/wp\/v2\/media?parent=17860"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ventsystems.de\/en\/wp-json\/wp\/v2\/categories?post=17860"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ventsystems.de\/en\/wp-json\/wp\/v2\/tags?post=17860"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}Calculating voltage drop simply<\/h2>\n\n\n\n
Installation and connection<\/h2>\n\n\n\n
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Typical mistakes<\/h2>\n\n\n\n
Mistake<\/th> Consequence<\/th><\/tr><\/thead> Cross-section too small on a long cable<\/td> Drive moves slowly or stops<\/td><\/tr> Plus and minus swapped (24 V)<\/td> Drive moves in the wrong direction<\/td><\/tr> No slack for cable movement<\/td> Cable breaks after a while<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n Frequently asked questions<\/h2>\n\n\n\n
Which cable should I use for a 24 V window drive?<\/h3>\n\n\n\n
May I shorten the supply cable?<\/h3>\n\n\n\n