Sices HS 315, Техническое руководство

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38 Technical Handbook
The system can efficiently compensate for both positive and negative potentials, ranging
between -2.7VDC and +4VDC, with sensors resistance values of 100 ohms. The range of
compensation increases for lower resistance values and decreases for higher values of
resistance, being optimized for the resistance values of the sensors in normal operating
conditions of the system.
The measure of the voltage with respect to the GND terminal is displayed on page S.15, under
item JM1; the measuring range of the system, and therefore the value indicated, can be higher
than the one useful for compensation, mentioned above.
The input measures the potential of the common ground point (negative) of the resistive
sensors, which for the sensors mounted on the engine is represented directly by the engine
itself or the chassis of the gen-set; JM-1 can therefore be connected to a grounding system or
to a bolt on the engine.
If the minus of one or several sensors is isolated from the engine or the gen-set chassis, for
example in the case of floats for fuel level measurement mounted on the plastic tanks or
electrically separated from the gen-set, you need to connect the JM-1 to the return of the
sensor and also to the negative electric mass of the engine or to the negative limit of the
starting battery.
Note: this connection should be made using a dedicated wire having the shortest
possible length. Avoid making the wire lies near high power and high voltage cable.
The input has a useful resistance measurement range between 0 and 1500 ohm; within this
range the measurement error guaranteed is less than 1%, with a voltage to the JM-1 terminal
with respect to the GND=0. Higher resistance values can be measured, although with
gradually decreasing precision.
The input has a useful resistance measurement range between 0 and 2000 ohm; within this
range the measurement error guaranteed is less than 1%, with a voltage to the JM-1 terminal
with respect to the GND=0. Higher resistance values can be measured, although with
gradually decreasing precision.
The input has a useful resistance measurement range between 0 and 1700 ohm; within this
range the measurement error guaranteed is less than 1%, with a voltage to the JM-1 terminal
with respect to the GND=0. Higher resistance values can be measured, although with
gradually decreasing precision.
To use the previously described analogue input as digital ones, simply configure the input with
the function AIF.0100. To activate the input, connect the its terminal to GND. To deactivate
the input, leave its input unconnected.
To use the previous input to acquire measures of pressure, temperature or level, normally the
operator must manually configure the relations between the ohms measured from the sensors
and the related °C, bar or %. For some commonly used VDO sensors, the conversions points
are still stored into the controller. The characteristics of these sensors are:
VDO TEMPERATURE SENSORS
0°C 1800 ohms
50°C 195 ohms