SIMATIC HMI KTP400 Comfort 4-inch Key/Touch Panel, PROFINET and MPI/PROFIBUS DP (6AV2124-2DC01-0AX0) CAN Electric — Industrial Automation Parts Supplier

A 4-inch door that gives operators a choice of hand

Some machines need more than a screen but less than a full keypad station. The KTP400 puts a resistive touch layer and four lit keys behind the same small bezel, so a worker can tap through menus one moment and hit Start or Acknowledge the next without taking eyes off the process. That split — navigation on glass, the critical few controls as keys — is the reason the type exists beside the keys-only KP400 and the touch-only TP400 of the same size.

Thirty-two virtual keys on the glass, wired straight to the PLC

Beyond the four physical keys, the touch surface can host up to 32 direct touch keys, each mapped as an S7 input peripheral. In effect the panel becomes a configurable membrane keypad that you draw where you need it, with no extra hardware — useful when the fixed four keys are not enough but a separate keypad station would be overkill. The lit physical keys still carry status, while the on-screen keys carry the rest of the button map.

For a project that is touch only, the Comfort PRO range and the larger Comfort touch panels cover it; for a panel that is keys only, the KP400 Comfort is the sibling. The KTP400 is the choice when you want both on the smallest footprint Siemens makes in the Comfort line.

Data per the Siemens product documentation and Industry Mall entry. The cutout, front dimensions and depth are from the mounting instructions — cut the enclosure only after the current data sheet is checked, because plate thickness and flatness decide whether the front seal actually seals.

Navigation on glass, commitment on keys

A touch layer is unbeatable for moving through screens and entering values; a physical key is unbeatable for an action that must be deliberate and confirmed by feel. The KTP400 keeps both in the same opening, so a guarded Start, Acknowledge or mode-select lives on a key the operator finds by touch in low light, while everything else stays a tap away. Unlike a touch-only panel, a glove or a smudge does not block the controls that matter most.

Hazardous-area and marine rated, at the smallest size

The nameplate carries ATEX/IECEx Zone 2/22, Division 2 certifications and full marine type approval (GL, ABS, BV, DNV, LRS, NK) — the same hazardous-area and classed-vessel coverage found on the larger Comfort panels, yet in a unit under 0.7 kg that fits the most confined doors. For a cell where a plain panel would not be accepted, the KTP400 brings that approval down to 4 inches.

The four keys versus the thirty-two touch keys

The four lit function keys are fixed hardware; the touch layer can present up to 32 direct touch keys mapped as S7 inputs, letting the screen become a custom keypad without adding a membrane. The two together cover a small machine comfortably: four permanent controls plus a flexible set that changes with the recipe, all inside one cutout.

The two are different device types in the same 4-inch Comfort family: the KTP400 adds a touch layer that the KP400 does not have, and the KP400 carries more dedicated function keys. Pick the combination when operators also tap through screens; pick the keys-only panel when the glass would only get in the way.

Same-model swap: keep the opening, restore the project

Four things decide whether the machine restarts on the same shift: cutout, depth behind the door, 24 V supply, and the project. With a known-good project on an SD card, a replacement needs no laptop at the machine — insert the card and load. Without one, an engineering seat has to open, recompile and download, so put that resource next to the electrician.

Moving to Unified: no same-size key-and-touch successor

Unlike the 7-inch and larger Comfort sizes, the 4-inch class has no same-size Unified Comfort panel that keeps both touch and keys. The closest 4-inch option is the 6AV2123-3DB32-0AW0, the MTP400 Unified Basic — a touch-only Basic-tier panel at 800 × 480, or you step up to the 7-inch MTP700 Unified Comfort (6AV2128-3GB06-0AX0). Because none keeps physical keys, a station that still needs them adds a KP8 (eight-button) or KP32 (thirty-two-button) key module on PROFINET.

What else changes when you cross that line

The platform moves from Windows CE 6.0 to the Linux-based Unified system, the engineering tool moves from WinCC Comfort V11 to WinCC Unified (Basic or Comfort depending on the target), and the device type in the project changes. Screens do not port one to one, so the upgrade is a project with a schedule, not a download. Treat the keypad decision as part of the migration plan.

Successor assignment and the KP8/KP32 option follow the Siemens status-change notice and the Eichler migration table for the 4-inch Comfort devices. Confirm the exact successor number, the cutout difference and the key-module fit against the current Siemens catalogue before ordering — the panel and the key module are separate order numbers.

The panel couples to SIMATIC S7-1200, S7-1500 and S7-300/400 over PROFINET or MPI/PROFIBUS DP, with Modbus TCP/IP and EtherNet/IP for third-party controllers. The PROFINET port includes an integrated switch, so a line or ring topology connects without an external switch in the cabinet. The 4-inch KP400 Comfort is the keys-only sibling, and the Comfort PRO range is the sealed, larger-screen family for washdown or outdoor cells.

How to order

• Email sales@can-electric.com with the order number, quantity, delivery country, and whether you are replacing a unit or stocking spares.
• State the condition you need — new, new-surplus or refurbished is written on the quote, not implied. For a running machine, send the hardware details from the old nameplate.
• The type is in phase-out, so availability comes from channel stock and is confirmed per order; prices are USD and ship from Hong Kong by DHL.