17
Section 5: Setting Up Transducers
The I.D. will be blanked, and the in-
put channel type will again be dis-
played in the transducer menu.
Reading a Transducer
The
READ
function is common to
all of the transducer menus. Press F1
to
READ
a value from the input
channel’s transducer.
The HERMIT 2000 will power the
input channel and take a transducer
reading . . .
. . . then display the result in the pro-
grammed units. The display format
will vary depending on the data type
of the input channel.
Press
ENTER
to take repeated read-
ings from the same transducer.
Use the
SCAN
keys to take readings
on other input channels.
This message means the HERMIT
2000 cannot obtain a valid reading.
Make sure the transducer is con-
nected to the proper input channel and that all connections are se-
cure.
Press
CLEAR
to return to the trans-
ducer menus.
Note:
Transducers will not read correctly until all of the parameters
contained in their corresponding menus have been programmed.
Programming Function Types
The parameters for a function type
input are contained in two menus.
Press
F4
in the main menu to access
the second menu.
Press
CLEAR
to return to the main
menu.
There are four transducer
parameters that you must
enter for a function type.
These parameters may be
found on the cable reel, or
on a data tag attached to the
cable. Use the column la-
beled “Quadratic Coeffi-
cients.”
• LIN
Linearity — Set to zero if not specified by the transducer
manufacturer.
• SCALE
Scale factor — Set as specified by the manufacturer; this
value should not be zero for a pressure transducer.
• OFFS
Offset — Set to zero if not specified.
• DELAY
Warmup delay — For an In-Situ transducer, set to 50
mSEC unless specified otherwise. You will probably have to de-
termine this value by experiment for third-party transducers.
Re-
minder
: During the first ten minutes of log sampling, the HER-
MIT 2000 uses a warmup delay of 50 mSEC, regardless of the
delay programmed. If you’ve selected the log sample mode, make
certain that your transducers are compatible with this require-
ment.
The unit will check that the sum of
the delays does not exceed the selected
sample rate. (This is only likely to be
a problem with third-party XDs and
a very fast LIN2 sample rate.) This error message means you need to
use shorter delays if possible, or a longer sample rate.
When you have entered all of the parameters, connect the trans-
ducer to its input channel and use the
READ
function in the trans-
ducer menu to verify proper operation.
The HERMIT 2000 computes function readings as follows:
READING = LX
2
+ SX + O
where
X =
Normalized* transducer value (0-1)
L =
Linearity
S =
Scale factor in units full scale
O =
Offset
*
Transducer reading (in mA) minus 4 divided by 16
The units of the linearity, scale, and offset parameters determine the
units of the reading. Readings in units other than those specified by
the manufacturer can be obtained by multiplying or dividing the
linearity, scale, and offset by the appropriate conversion factor be-
fore entering them into the HERMIT 2000.
Input 1: Function
READ I.D.
more
Input 1: Function
READ I.D.
more
Input 1: Function
Busy...
Input 1: Function
22.070
Input 1: Function
22.070
Input 2: Level (F)
(25.465)
16.239
Input 1: Function
Not connected?
Input 1: Function
READ I.D.
more
Input 1: Function
READ I.D.
more
Input 1: Function
LIN SCALE OFFS DELAY
Test 0: DELAYS>RATE!
(cant start/step)