Blaze EMS-2 Operating Manual
Page 54
10.4 Temperature senders
VDO Resistive senders:
The EMS-2 supports the VDO 120ºC and 150ºC thermistor automotive senders. The
internal pull up resistor dip switch for the resistive temperature sender input must be in the “ON” position.
MGL NTC resistive senders:
A suitable sender with the same thread used by Rotax can be obtained from MGL
Avionics (manufacturer Echlin). The internal pull up resistor dip switch for the resistive temperature sender input must be
in the “ON” position.
Most NTC senders require a single wire connected as shown in the installation diagram. The sender is grounded via the
engine block. The ground terminal of the gauge input should be connected to the engine block. Some NTC senders have
two wires. In this case it is not required that the sender housing itself is connected to the engine block. Wire the second
wire to the reference ground terminal.
MGL Precision senders (On Semiconductors LM335):
These are senders containing a semiconductor
temperature measurement device. They can be used for water or oil temperature. These senders are available in two
types: an encapsulated version with a brass housing suitable for Rotax thread; a second uncommitted version contains
only the sensor itself. This can be conveniently mounted inside an existing sender housing after you remove the original
insides of the sender. This is intended to give you a solution for unusual or difficult to obtain senders. The internal pull up
resistor dip switch for the resistive temperature sender input must be in the “ON” position.
Connect the green wire to ground and the red wire to the analog input channel.
Westach Resistive senders:
The EMS-2 supports the Westach 399 series senders. The internal pull up resistor
dip switch for the resistive temperature sender input must be in the “ON” position.
User defined senders:
The EMS-2 has a user sender calibration feature that can be customized for senders not
listed above.
10.5 Pressure senders
VDO Resistive senders:
The EMS-2 includes linearisation curves for the VDO 2, 5 and 10 Bar pressure senders.
The internal pull up resistor dip switch for the resistive pressure sender input must be in the “ON” position.
4-20mA Pressure Senders:
The EMS-2 supports the 4-20mA pressure sender as used in Rotax 912/914 engines
The supplied 100Ohm 1/4W resistor must be connected across the analog input channel to ground. The internal pull up
resistor dip switch for the 4-20mA current sender input must be in the “OFF” position. Only channel 1 to 3 can be used for
the 4-20mA pressure sender if using the internal measurement circuit and only the OILP, AUX 1 and AUX 2 can be used
if using the external RDAC.
Voltage output pressure senders:
The EMS-2 includes linearisation curves for the UMA N/T 1EU07, N/T
1EU35, N/T 1EU70, N/T 1EU70A, N/T 1EU100 and N/T 1EU150 pressure senders. The EMS-2 also has a 0.5-4.5V
sender selection. The internal pull up resistor dip switch for the 0.5-4.5V sender input must be in the “OFF” position.
User defined senders:
The EMS-2 has a user sender calibration feature that can be customized for Resistive, 4-
20mA as well as Voltage output senders.