Innovate Motorsports TC-4 - Manual (Page 6)

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Most Thermocouple probes are of the “grounded junction” type. This means that the “hot
junction” is also connected to the probe’s body. As this body is connected for example to the
exhaust manifold, the sensor wires are essentially grounded through that. The same would be
true if a home-made thermocouple junction is used as described above by twisting the wires and
if that wire-twist is connected to some grounded engine part. If the twisted ends would be
grounded, untwist them first and clamp the separately but close together. Otherwise the clamping
metal part can short out part of the thermocouple voltage. See below:
The TC-4 will work with either isolated or grounded junction thermocouples.
There are four GND connections. The two closest to the 5V terminal can be used for
thermocouple shielding. The GND terminals next to the TC4- terminal are no-connects so they
are not to be used.
5. The Innovate Log-Chain concept
LogWorks 2.0 has the capability to log, display and analyze up to 32 engine parameters. Most
users will use less though. Each of the MTS components reads between 1 and 6 engine
parameters. To interface a multitude of MTS components to LogWorks with a single connection,
the Innovate LogChain concept was introduced.
The TC-4 can be used as a MTS component in a Log-Chain.
Each of the MTS components has two serial ports (except the LM-1, which has only one). One
serial port is designated as IN-port, the other as OUT port. The OUT-port of one device is
connected to the IN-port of the next device and so on. This way devices can be ‘daisy-chained’ to
build a log-chain for up to 32 channels total. The OUT-port of the last device is connected to the
computer for logging or downloading of logged data.
The device that’s first in the chain is special. It determines the logging sample rate. The first
device in the chain sends a data packet containing its channel data (a sample) to the next device
(downstream, left to right in the diagram) every 81.92 milliseconds. The next device appends its
data to that packet and hands that packet to the next device downstream and so on. At each
device the packet grows in length. The devices in the chain synchronize their sampling of the
engine parameters to the packets, so that all the channels in a packet together represent the
same instance in time. At the downstream end of the log chain (OUT-port of the last device) a
computer or external logger can be connected to store or display the stream data. The XD-1
display is such a device.