Power Supply for MX8/MX9 Modules
MX1 central stations provide power for CAN bus participants. This
power outlet is internally protected with a 2A fuse.
Larger layouts with many CAN bus components require a external power
supply. ZIMO recommends a rule of thumb of approximately 10-12 modules
and a few more cabs. There are 2 reasons for external power supply
- The overall power requirement of all MX modules is over 2A. One
MX9 requires roughly 135-150mA
- The length of the CAN Bus cable causes too much voltage loss.
Usually cables have 0,1mm2 wires. Pulling 1A or more over
100m cable would already loose 15V!!! This leads into unreliable
layout operation as the modules are underpowered! Especially spike
power requirements may cause hard to detect problems.
The external power source is best connected by opening the CAN bus
cable (+) side. All modules behind that point will be powered
externally. The voltage should be a few volts ober track signal. A good
value is about 30 volts. |