Specifications

SVI Trucks

Freightliner 4-Door Demo

SVI #917 01/05/15

12 VOLT MULTIPLEX CONTROL CENTER

The apparatus shall be equipped with a Weldon V-MUX multiplexed 12 volt electrical system that will provide

complete diagnostic capability, No Exception. The system shall have the capability of delivering multiple signals

via a CAN bus, utilizing specifications set forth by SAE J1939. The system shall be node based to maximize

stability so that failure of one node does not affect the operation of the other nodes. The system shall use

shielded twisted-pair wire for transmission of system function signals. The shielded wire shall provide protection

against EMI and RFI noise interruptions.

The multiplex system shall be responsible for providing power management functions as well as load shedding.

The warning light system shall be controlled by the multiplex system. The system shall be capable of displaying

text and/or graphic messages on a display module. The system shall be based on solid-state technology and

shall include self-contained diagnostic indicators.

Outputs:

The outputs shall perform all the following items without added modules to perform any of the tasks;

1. Load Shedding: The system shall have the capability to load shed with 8 levels any output. This means you

can specify which outputs (barring NFPA restrictions) you would like load shed. Level 1 12.9v, Level 2 12.5V,

Level 3 - 12.1V, Level 4 - 11.7V, Level 5 11.3V, Level 6 10.9V, Level 7 10.5, Level 8 10.1. Unlike conventional

load shedding devices you can assign a level to any or all outputs.

2. Load Sequencing: The system shall be able to sequence from 0 8 levels any output. With 0 being no delay

and 1 being a 1 second delay, 2 being a 2 second delay and so on. Sequencing reduces the amount of

voltage spikes and drops on your vehicle, and can help limit damage to your charging system.

3. Output Device: The system shall have solid-state output devices. Each solid-state output shall be a MOS-FET

(Metal Oxide Semiconductor - Field Effect Transistors); MOS-FETs are solid-state devices with no moving

parts to wear out. A typical relay when loaded to spec has a life of 100,000 cycles. The life of a FET is more

than 100 times that of a relay.

4. Flashing Outputs: The system shall be able to flash any output in either A or B phase, and logic is used to shut

down needed outputs in park, or any one of several combined interlocks. The flash rate can be selected at

either 80, 160 or 200 FPM. This means any light can be specified with a multiplex truck with no need to add

flashers. Flashing outputs can also be used to warn of problems or other unique idea you may come up with.

5. PWM: The modules shall have the ability to PWM at some outputs so that a headlight PWM module is not

needed.

6. Diagnostics: An output should be able to detect either a short or open circuit. The system should be able

report in “real time” a text based message that points the maintenance person to a specific output.

Inputs:

1. The inputs shall have the ability to switch by a ground or vbatt signal.

2. The inputs shall be filtered for noise suppression via hardware and software so that RF or dirty power will not

trick an input into changing its status.

Auto-Throttle:

The multiplex system shall be able to perform automatic high idle via a network gateway or by using an existing

output on a module to provide the proper signals to an OEM Engine ECU. This task should be handled with

existing inputs and outputs.