{"id":41635,"date":"2026-02-18T12:52:51","date_gmt":"2026-02-18T11:52:51","guid":{"rendered":"https:\/\/onvolt.pl\/produkt\/dc-12-40a-relay-for-heating-mats-with-base\/"},"modified":"2026-02-18T12:52:51","modified_gmt":"2026-02-18T11:52:51","slug":"dc-12-40a-relay-for-heating-mats-with-base","status":"publish","type":"product","link":"https:\/\/onvolt.pl\/en\/products\/dc-12-40a-relay-for-heating-mats-with-base\/","title":{"rendered":"DC 12 40A relay for heating mats with base"},"content":{"rendered":"<p><strong>Relay for controlling 12V heating mats<\/strong><\/p>\n<p>The relay enables safe connection of a set of heating mats to a BMS equipped with a heating mat control function.<\/p>\n<p>Typically, BMS &#8220;Heat&#8221; outputs can carry a maximum current of 2-3A, hence the need to use a relay.<\/p>\n<p>The set of <a href=\"https:\/\/onvolt.pl\/en\/products\/heating-mat-170x200mm-12v-27w-for-lifepo4-cells-280-360ah\/\">heating mats<\/a> for a 12V battery that we recommend has a power of 5x27W, which translates into a current of over 11A.<\/p>\n<p>This is definitely too much to connect directly to the BMS.<\/p>\n<p>The offered relay allows for transfer of current up to 40A.<\/p>\n<p>It is equipped with a ready-made base with appropriately selected cable cross-sections (16 and 22AWG).<\/p>\n<p>Additionally, a diode is used to protect the BMS output.<\/p>\n<p><strong>IMPORTANT: <\/strong><\/p>\n<p>Due to the presence of the diode, the correct polarity of the connection must be observed &#8211; the white wire is the positive coil control.<\/p>\n<ul style=\"margin-top: 0px; margin-bottom: 1rem; padding-left: 20px; font-family: Manrope, sans-serif; font-size: 16px; font-style: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal;\">\n<li>Lifespan: 10,000,000 switching operations<\/li>\n<li>Switch-on time approx. 10ms <\/li>\n<li>Length of socket wires approx. 19cm <\/li>\n<li>Relay dimensions 28.5 x 28.5 x 25 mm<\/li>\n<\/ul>\n<ul style=\"margin-top: 0px; margin-bottom: 1rem; padding-left: 20px; font-family: Manrope, sans-serif; font-size: 16px; font-style: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal;\">\n<li><strong style=\"font-weight: bolder;\">The relay is very solidly made and has copper-plated contacts.<\/strong><\/li>\n<li><strong style=\"font-weight: bolder;\">Fits very well with the socket<\/strong><\/li>\n<li><strong style=\"font-weight: bolder;\">The thick 16AWG and 22AWG socket wires allow for the real transfer of high current.<\/strong><\/li>\n<\/ul>\n<p style=\"margin-top: 0px; margin-bottom: 1rem; font-size: 0.9375rem; font-weight: 400; font-family: Manrope, sans-serif; font-style: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal;\"><strong style=\"font-weight: bolder;\">The relay has 5 contacts<\/strong><\/p>\n<ul style=\"margin-top: 0px; margin-bottom: 1rem; padding-left: 20px; font-family: Manrope, sans-serif; font-size: 16px; font-style: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal;\">\n<li>we connect the coil switching voltage to contacts 85, 86 (black and white wires).<strong style=\"font-weight: bolder;\">(white is a plus).<\/strong><\/li>\n<li>the coil shorts contacts 30 and 87 (blue and yellow wires) NO<\/li>\n<li>the coil opens contacts 30 and 87a (blue and red wires) NC<\/li>\n<li>the protection diode is connected in a reverse direction between pin 85\/86.<\/li>\n<\/ul>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Relay for controlling 12V heating mats The relay enables safe connection of a set of heating mats to a BMS equipped with a heating mat control function. Typically, BMS &#8220;Heat&#8221; outputs can carry a maximum current of 2-3A, hence the need to use a relay. The set of heating mats for a 12V battery that [&hellip;]<\/p>\n","protected":false},"featured_media":38894,"template":"","meta":{"_et_pb_use_builder":"","_et_pb_old_content":"","_et_gb_content_width":""},"product_brand":[],"product_cat":[1958,1916],"product_tag":[],"class_list":["post-41635","product","type-product","status-publish","has-post-thumbnail","product_cat-cell-heating-battery-heating","product_cat-new-in-en","pa_maks-ciagly-prad-rozladown-40a-en","pa_napiecie-akumulatora-128v-4s-en","pa_napiecie-akumulatora-148v-4s-en","first","instock","taxable","shipping-taxable","purchasable","product-type-simple"],"_links":{"self":[{"href":"https:\/\/onvolt.pl\/en\/wp-json\/wp\/v2\/product\/41635","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/onvolt.pl\/en\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/onvolt.pl\/en\/wp-json\/wp\/v2\/types\/product"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/onvolt.pl\/en\/wp-json\/wp\/v2\/media\/38894"}],"wp:attachment":[{"href":"https:\/\/onvolt.pl\/en\/wp-json\/wp\/v2\/media?parent=41635"}],"wp:term":[{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/onvolt.pl\/en\/wp-json\/wp\/v2\/product_brand?post=41635"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/onvolt.pl\/en\/wp-json\/wp\/v2\/product_cat?post=41635"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/onvolt.pl\/en\/wp-json\/wp\/v2\/product_tag?post=41635"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}