{"id":3252,"date":"2026-09-25T11:47:19","date_gmt":"2026-09-25T09:47:19","guid":{"rendered":"https:\/\/cle-automazioni.com\/?post_type=product&p=3252"},"modified":"2026-10-06T10:16:22","modified_gmt":"2026-10-06T08:16:22","slug":"crm-1c-rs232-single-mode-optical-fiber-converter","status":"publish","type":"product","link":"https:\/\/cle-automazioni.com\/en\/crm-1c-rs232-single-mode-optical-fiber-converter\/","title":{"rendered":"RS232 single-mode optical fiber converter – CRM\/1C"},"content":{"rendered":"

CRM\/1C is an RS232 single-mode optical fiber converter that converts RS232<\/a> electrical serial bus standard to single-mode optical fiber with an SC connector. It can be used to extend the transmission distance of a serial communication or to isolate network branches. It can be mounted on a control panel with a 35 mm DIN rail and it’s very compact, only 1 DIN module.<\/p>\n

CRM\/1C RS232 single-mode optical fiber converter accepts a wide range of low-voltage AC and DC power supplies; it is fully Plug & Play and requires no drivers or DIP switches. The RS232 serial interface operates in full-duplex mode and automatically detects the transmission speed up to 250 kbps, making it easy to install in any new or existing system.<\/p>\n

 <\/p>\n

What is an RS232 to optical fiber converter used for?<\/h4>\n

An RS232 single-mode optical fiber converter is typically used to create a communication backbone between two or more buildings in an RS232 serial bus network. When multi-mode fiber is not enough, single-mode optical fiber is the right choice, because the reachable distance is much greater. The transmission distance can reach 20 km with single-mode optical fiber, against 2 km with multimode glass fiber. Such distances are often unnecessary, but an RS232 single-mode optical fiber converter can be useful when the fiber has already been laid, and single-mode fiber is increasingly common because it is more versatile, as it can also be used for data transmission at several Gbps.<\/p>\n

There are also environments where electrical equipment is prohibited, such as swimming pools, saunas, and buildings at risk of fire, where fiber optics therefore become necessary.<\/p>\n

 <\/p>\n

Advantages<\/h4>\n

In a system, it is good practice to install an RS232 single-mode optical fiber converter at the beginning of a fiber run. This helps reduce issues related to ground potential differences or possible power surges. Optical fiber is a perfect electrical insulator and therefore protects the RS232 bus from the propagation of lightning strikes or other atmospheric discharges.<\/p>\n

Fiber optics isolate various branches of a network, such as the floors of a hotel or sections of a photovoltaic system, from electromagnetic interference (EMI) and power surges. Electromagnetic interference is common in these environments, so it is good practice to install two or more optical-to-electrical converters to ensure signal integrity.<\/p>\n

Furthermore, an RS232 single-mode optical fiber converter allows for the regeneration of the electrical signal, thereby improving communication quality.<\/p>\n

 <\/p>\n

Protocol<\/h4>\n

CRM\/1C RS232 single-mode optical fiber converter is completely independent of the protocol used. This means that the converter is transparent to the communication and can be used with any proprietary protocol.<\/p>\n

This is possible because the converter operates at the logical levels, rather than at the protocol level itself. Therefore, this RS232 single-mode optical fiber converter can also be used in complex networks where multiple protocols are present simultaneously on the same RS232 bus.<\/p>\n

 <\/p>\n

Installation<\/h4>\n

Single-mode optical fiber is more difficult to install than multi-mode fiber (synthetic or glass), because it requires dedicated termination tools and softer bend radius.<\/p>\n

However, the versatility of single-mode fiber is quickly gaining ground and replacing multimode optical fiber in new installations, which makes an RS232 single-mode optical fiber converter necessary. The push-pull SC connector is very easy to use, and its snap-in latch ensures a secure connection.<\/p>\n

For these reasons, single-mode optical fiber is often used only as a communication backbone over long distances, while multi-mode or synthetic plastic optical fiber (POF) is preferred for shorter runs because it is easier to install.<\/p>\n

 <\/p>\n

Versatility<\/h4>\n

The RS232 single-mode optical fiber converter is available with other combinations of serial and fiber optic standards. CRM\/1S<\/a> and CRM\/1V<\/a> converters, for example, accept synthetic fiber with a screw-type connector or multi-mode glass fiber with an ST connector, respectively. CMM\/1C<\/a> and CFM\/1C<\/a>, on the other hand, are suitable for various serial standards, namely RS485 and RS422.<\/p>\n

All combinations of serial standards and optical fiber types are available in the catalog; however, special requests (such as higher data rates) can be made via the contact form.<\/p>\n","protected":false},"excerpt":{"rendered":"

CRM\/1C is an RS232 single-mode optical fiber converter, used when the serial link needs to exceed the effective range of copper wiring or pass through an area with electrical interference. It mounts on a 35 mm DIN rail, occupying a single module, and automatically detects baud rates up to 250 kbps, allowing it to be integrated into an existing system without any configuration or DIP switches.<\/p>\n

 <\/p>\n

It is completely protocol-transparent, so it can be used with any proprietary protocol operating on an RS232 bus.<\/p>\n

 <\/p>\n

FAQ<\/h4>\n

What is the maximum transmission distance?<\/strong><\/p>\n

Up to 20 km per single point-to-point link.<\/p>\n

 <\/p>\n

Single-mode or multi-mode fiber: which is better?<\/strong><\/p>\n

It depends on the application. Single-mode fiber is required for long distances, but multi-mode fiber is easier to use.<\/p>\n

 <\/p>\n

Can I connect it to CRM\/1V?<\/strong><\/p>\n

No, the fiber is different and not compatible, and so is the wavelength.<\/p>\n

 <\/p>\n

Which fiber and connectors are needed?<\/strong><\/p>\n

One 9\/125 \u00b5m single-mode fiber for TX and one for RX, with a duplex SC connector or two separate simplex SC connectors.<\/p>\n

 <\/p>\n

Does it need to be configured?<\/strong><\/p>\n

No, it automatically detects the baud rate up to 250 kbps, and accepts a wide range of low-voltage AC and DC power supplies.<\/p>\n","protected":false},"featured_media":3259,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_acf_changed":false},"product_brand":[303],"product_cat":[257,265,262],"product_tag":[273,274,293,280,275,294],"class_list":["post-3252","product","type-product","status-publish","has-post-thumbnail","product_brand-cle-automazioni","product_cat-isolation","product_cat-optical-fiber","product_cat-rs232-en","product_tag-converter","product_tag-din-rail","product_tag-glass-fiber","product_tag-optical-fiber","product_tag-rs232","product_tag-single-mode-fiber","first","instock","shipping-taxable","product-type-simple"],"acf":[],"_links":{"self":[{"href":"https:\/\/cle-automazioni.com\/en\/wp-json\/wp\/v2\/product\/3252","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/cle-automazioni.com\/en\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/cle-automazioni.com\/en\/wp-json\/wp\/v2\/types\/product"}],"replies":[{"embeddable":true,"href":"https:\/\/cle-automazioni.com\/en\/wp-json\/wp\/v2\/comments?post=3252"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/cle-automazioni.com\/en\/wp-json\/wp\/v2\/media\/3259"}],"wp:attachment":[{"href":"https:\/\/cle-automazioni.com\/en\/wp-json\/wp\/v2\/media?parent=3252"}],"wp:term":[{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/cle-automazioni.com\/en\/wp-json\/wp\/v2\/product_brand?post=3252"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/cle-automazioni.com\/en\/wp-json\/wp\/v2\/product_cat?post=3252"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/cle-automazioni.com\/en\/wp-json\/wp\/v2\/product_tag?post=3252"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}