
ZENO
®
-3200 USER MANUAL
Coastal Environmental Systems (206) 682-6048
Page 170
The ZENO
®
-3200 will turn on a switched voltage before the start of a
Sample Interval when the sensor requires time to warm up.
If the Sensor Warm-up Time is set to a value longer than the Sample
Interval, the ZENO
®
-3200 will always keep the designated Switched Voltage
on.
If more than one sensor is on the same Switched Voltage and all require
warm-up time, the Switched Voltage will be turned on based upon the
sensor with the longest warm-up time.
No warm-up time will occur if no Switched Voltage is specified for the
sensor.
The valid range of values for the Sensor Warm-up Time (Line Item #9) is 0 to 255 seconds.
10.3.12. Using Excitation Voltage and Returns To Control Sensor Power
The Excitation Voltage can be used to cancel errors due to reference voltage
drift in ratio-metric measurements, such as bridge sensors, because the
Excitation Voltage is referenced to the same voltage reference as the A/D
converter.
The Excitation Voltage outputs are marked EXC + on the ZENO
®
-3200 Front Panel.
189
The Excitation Voltage can be set to one of four values in Line Item #7 in the Sensor Menu. The values
are described in the following table.
Line Item
#7 Value
Excitation Voltage Setting
Comments
0 No excitation voltage (0 V DC) N/A
1 1.25 V DC Use if sensor self-heating is a problem
2 2.50 V DC Use for highest accuracy
3 5.00 V DC Use if noise pickup is severe
The sensor's positive power terminal is connected to one of the outputs marked EXC + on the ZENO
®
-
3200 Front Panel.
190
The sensor's negative power terminal is connected to one of the grounds marked AGND or one of the five
terminals labeled as SWITCHED EXCITATION RETURNS on the ZENO
®
-3200 Front Panel.
191
The
Switched Excitation Return Channels are labeled A, B, C, D or E. If one of the Excitation Voltage Return
Channels is used, then you need to specify which Switched Excitation Return Channel is being used in
Line Item #8 of the Sensor Menu.
189
Refer to Section 2.1.
190
Refer to Section 2.1.
191
Refer to Section 2.1.
Kommentare zu diesen Handbüchern