Locomotive and CTC-Modules

As with digital decoders, there is no universal CTC locomotive module either. The internal connections and space requirements of locomotives vary too much.

Common features of all CTC locomotive modules

Property Description
Input voltage approx. 9 V to 24 V DC, digital current or AC (with support capacitor)
WiFi module/processor Espressif ESP32
Interfaces CTC-IR receiver ,
I2C or CTC-NFC reader ,
SUSI3 or MicroSUSI socket

From February 2025, we will include a TVS diode with all locomotive modules for gauge G. For smaller gauges, it should be sufficient if TVS diodes are installed in the track. See the section "Overvoltage protection" on the page "Power supply and router" .

Overview of CTC locomotive modules

Locomotive modules

CTC locomotive module Optimized for Dimensions Motor output Switching outputs Sound socket Max. total current
CTC-Loco-Module-XS3 Analog N gauge 13 x 9.5 mm 1x 1.0 A 2 half-bridges, 2x LED MicroSUSI 2 A
CTC-Loco-Module-S3 PluX16 20 x 10 mm 1x 1.0 A 4 half-bridges MicroSUSI 2 A
NEM-652 (8-pin) 20 x 10 mm 1x 1.0 A 3 half-bridges (2x light, AUX) MicroSUSI 2 A
NEM-651 (6-pin) 20 x 10 mm 1x 1.0 A 2 half-bridges (2x light) MicroSUSI 2 A
Cable, 2 AUX 20 x 10 mm 1x 1.0 A 4 half-bridges (2x light, 2x AUX) MicroSUSI 2 A
Solder pads, 2 AUX 20 x 10 mm 1x 1.0 A 4 half-bridges (2x light, 2x AUX) MicroSUSI 2 A
CTC-Loco-Module-DCC (S3) DCC 20 x 10 mm DCC total 1.0 A - MicroSUSI 2 A
CTC-Loco-Module-M3 PluX22 30 x 15.5 mm 1x 1.0 A 8 half-bridges SUSI3 2 A
21mtc (Märklin) 30 x 15.5 mm 1x 1.0 A 6 half-bridges + 2 digital SUSI3 2 A
NEM-652 (8-pin) 30 x 15.5 mm 1x 1.0 A 3 half-bridges (2x light, AUX) SUSI3 2 A
NEM-651 (6-pin) 30 x 15.5 mm 1x 1.0 A 2 half-bridges (2x light) SUSI3 2 A
Cable, 2 to 6 AUX 30 x 15.5 mm 1x 1.0 A 4 to 8 half-bridges SUSI3 2 A
CTC-Loco-Module-DCC (M3) DCC 30 x 15.5 mm DCC total 1.0 A - SUSI3 2 A
CTC-Loco-Module-21mtc (discontinued) 21mtc (Märklin) 30 x 15.5 mm 1x 1.0 A 6 LowSide + 2 digital - 2 A
CTC-Loco-Module-G2 LGB / large gauges 78 x 30 mm 2x 1.0 A or 2x 2.0 A 6x 1.2 A LowSide
4x 2.5 A half-bridge 		SUSI3 15 A

No longer offered locomotive modules:

Notes:

  • Operating CTC locomotive modules on AC or unfiltered DC without a support capacitor will cause irreparable damage to the CTC module.
  • Switching outputs are differentiated by whether they switch ground or negative (LowSide) or the positive pole (HighSide). Especially with LED boards at the front, there is often a common line for one pole. It is then important whether the switching outputs of the locomotive module are designed as HighSide or LowSide.
  • A half-bridge can be switched between positive and negative poles but is never switched off. Especially so-called magnetic articles (e.g., uncouplers) can suffer permanent damage if the half-bridge is incorrectly configured and should therefore not be connected to a half-bridge.
  • A separate power supply module is required for servos.
  • If consumers (lamps, smoke generators, ...) in the locomotive have a connection to the housing, they may only be connected to the CTC module via a protection diode.

Buffer capacitors

With our locomotive modules, we always supply matching buffer capacitors. In the shop, you can choose from the following:

Buffer capacitors 25 Volt Buffer capacitors 16 Volt

Capacity Max. voltage Size
6800 µF 25 Volt Diameter
2200 µF 25 Volt 25 mm, diameter 12.8 mm
1000 µF 25 Volt 20 mm, diameter 10 mm
560 µF 25 Volt 15.5 mm, diameter 5.5 mm
470 µF 25 Volt 12.5 mm, diameter 8 mm
470 µF 16 Volt 10.8 mm, diameter 6.3 mm
470 µF 16 Volt approx. 7.5 x 6.1 x 1.9 mm
330 µF 16 Volt approx. 7.5 x 4.8 x 4.4 mm

Locomotive conversion

On the Locomotive conversion page , you will find general information on locomotive conversion as well as various locomotive conversions documented in text and images. These are regularly updated.