DIN Rail
DIN Rail for Terminal Block Mounting
DIN rail is the standardized mounting strip that terminal blocks, along with circuit breakers, relays, and other panel components, snap onto inside a control cabinet or enclosure. Within Galco's terminal blocks category, rail selection isn't an afterthought to choosing the terminal blocks themselves - the rail profile a terminal block is designed for determines compatibility before wire gauge or pole count even comes into play. Mounting a terminal block designed for one rail profile onto another is a common and avoidable source of unsecured, unsafe installations.
TS35, also called top-hat rail, is the default choice unless a component datasheet specifies otherwise; its 35mm symmetrical profile accommodates the overwhelming majority of modern terminal blocks, circuit breakers, and control components. TS35 is available in two depths: 7.5mm for standard density terminal block runs, and 15mm where heavier components or denser panel layouts call for added rigidity. TS15, a narrower 15mm profile, is reserved for compact enclosures or auxiliary rail runs where panel space is genuinely constrained; TS35 terminal blocks will not clip onto TS15 rail, so the two aren't interchangeable based on available space alone. G32 (G-section) rail is an older, asymmetrical profile still found in legacy panels and heavier-duty applications, but it requires G-type components specifically - TS35 terminal blocks won't seat correctly on G-section rail, and mixing the two is a frequent procurement error during panel maintenance or expansion.
Once the rail profile is confirmed, retaining the terminal blocks on the rail is the next consideration. Terminal blocks aren't typically fixed permanently to DIN rail; they're held in place by end stops or end plates at each end of the run, which prevent the block assembly from sliding or loosening under vibration. For applications requiring additional bracing, sectioning, or accessories beyond basic mounting, Galco's terminal block accessories covers jumpers, markers, and mounting hardware specific to rail-mounted terminal assemblies. Material selection - zinc-plated steel for general industrial use, aluminum or stainless steel for corrosive or washdown environments - should match the panel's environmental exposure rather than defaulting to standard steel in every application. For control system components beyond terminal blocks, including relay and signal interface modules that also mount to standard DIN rail, see Galco's DIN rail interface modules.
URL: https://www.galco.com/products/connectors-cordsets-terminals/terminal-blocks/din-rail.htmlFrequently Asked Questions
How do I know which DIN rail profile my terminal blocks need?
Check the terminal block's datasheet or product listing for its specified mounting profile - if none is listed, TS35 is the safe default, since it's the profile the vast majority of modern terminal blocks are designed for. Measuring the rail itself rather than relying on visual comparison is more reliable when working with existing panels, since TS35, TS15, and G32 can be difficult to distinguish by sight alone, particularly between TS35 and the narrower G32 profile.
Can I mix TS35 and TS15 terminal blocks on the same panel?
Yes, but not on the same physical rail run - TS35 and TS15 terminal blocks require their respective rail profiles and won't clip securely onto the other. A panel can use both profiles in different sections (TS35 for primary component density, TS15 for auxiliary or space-constrained runs), but each rail segment needs to match the terminal blocks mounted to it. End stops should be used at the boundary between rail segments to keep each terminal block run properly secured.
Do I need 7.5mm or 15mm depth TS35 rail for my terminal block run?
Standard 7.5mm depth handles the majority of terminal block installations without issue and is the more space-efficient choice for dense panel layouts. The deeper 15mm variant adds rigidity and is worth specifying where the terminal block run is long, where the panel will experience significant vibration, or where heavier components share the same rail - the added depth reduces flexing under load that can loosen connections over time.