
Lake Shore Model 340 Temperature Controller User’s Manual
Instrument Programming
8-15
8.4.1.4 Viewing the Logged Data
To view the logged data on the display, highlight
View logged data
and press the
Enter
key. The
VIEW DATA LOG
screen will appear.
Record
Specifies the record number. The first record is numbered 1. Use the
s
or
t
key to increase or
to decrease the record number. The number keys followed by
Enter
can also be used to enter a
record number directly.
8.4.1.5 Dumping the Logged Data to the Serial I/O Port
Logged data can also be transferred to the Serial I/O port. Highlight
Dump logged data
and press the
Enter
key. The following
message will appear on the display.
To stop dumping, press the
Escape
key.
The dumped data has the following format.
<Timestamp>, <Point 1>, <Point2>, <Point3>, <Point4> [term]
where,
<Timestamp> Shows the timestamp of the record. Refer to the DATETIME? query for the string format.
<Point n>
The Model 340 decodes the stored data depending on the point type.
(1) Input
<value>,<status>
<value> is in either K or C or sensor unit depending on the input source. <status>
indicates input status and can have a value from 0 to 255. Each bit has its own
meaning as shown below.
Bit 7:
1 = Input is DISABLed.
Bit 6:
1 = Input has NOCURVe.
Bit 5:
1 = Input is S-OVER.
Bit 4:
1 = Input is S-ZERO.
Bit 3:
1 = Input is T-OVER.
Bit 2:
1 = Input is T-UNDR.
Bit 1:
1 = Old reading. (*)
Bit 0:
1 = Invalid reading.
(2) SP1/2 <value>
<value> is in either K or C or sensor unit depending on the setpoint unit.
(3) Out1
<value>,<current/power>,<heater range>
<value> is in %. <current/power> = 1 for current, 2 for power. <heater range>
indicates the heater range in W.
(4) Out2
<value>
<value> is in %.
(5) None
0.0
(*) This bit is typically set if the input is configured as one of Negative Voltage Coefficient Resistance
Temperature Device with constant voltage excitation and when its thermal compensation is ON. In this
situation, this bit is set in every other reading, which indicates 10 readings update per second.
[term]
Currently specified Serial Terminator.
8.4.1.6 Line Power Loss
When line power is lost while the Model 340 is logging data, it resumes the data log sequence when power is
restored, if the battery in the SRAM Data Card has enough voltage to keep the logged data.
VIEW DATA LOG
Record
1
of 28332
Date 12/15/2000 Time 14:37:20.370
Point Type Input Source Value
1: Input A TEMP K 284.945 K
2: SP1 285.000 K
3: Out1 + 69.1% @ 25W
4: Input A 0.55507 v
Dumping logged records...
Record 1 of 28332
Press ESCAPE to abort.