Advanced Measurement Technology 273A, User Manual

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Model 273A Potentiostat/Galvanostat User’s Manual
Example: To drop DELAY 2 from the scan sequence, key:
[DELAY 2] [PASS] [ENTER]
13. [SEC]: This key is used in conjunction with either of the DELAY keys to specify a delay
interval in seconds.
Example: To set a DELAY 1 interval of 100 s, key:
[DELAY 1] [1] [0] [0] [SEC] [ENTER]
14. [mV/SEC]: This key is used in conjunction with either of the DELAY keys to specify a delay
interval in drift units. Defining the delay in this manner is particularly well suited to
experiments where the specimen must be allowed to come to equilibrium before valid
measurements can be taken. The open-cell potential is monitored, allowing the drift rate to
be measured as it asymptotically approaches the rest potential. When the actual rate
becomes slower than the rate specified via the [mV/SEC] key, the delay interval ends. The
slower the specified drift rate, the longer the minimum delay time (the longer it takes to get a
valid drift-rate reading).
Example: To set a DELAY 2 drift rate of 0.01 mV/s, key:
[DELAY 2] [.] [0] [1] [mV/SEC] [ENTER]
15. [CELL OFF]: This key determines whether delay intervals specified in seconds will be done
open-cell or with the specified potential/current applied. The key is a toggle, that is, its state
(indicated by the alphanumeric display) reverses each time the key is pressed.
Example: To set an open-cell DELAY 1 of 100 s, key:
[DELAY 1] [1] [0] [0] [SEC] [CELL OFF] [ENTER]
16. [ENTER]: This key has two functions. First, it enters newly specified parameter values into
the setup program. Second, when not entering a parameter, it allows different kinds of
information to be scrolled through the bottom line of the display.
For example, when a setup parameter key is pressed, the set value is displayed, together
with the message, ENTER XXX (XXX signifies the parameter). The new value can then be
keyed and ENTER pressed, after which the new value will be displayed. Pressing ENTER
again clears the new value from the display and establishes the scroll mode, in which the
bottom display line scrolls through several possible display options, advancing once each
time the ENTER key is pressed. The choices are:
a. Second Display Line Blank.
b. Charge in Coulombs.
c. Log of I if LOG is Enabled.
d. Status of the Scan. Possibilities include:
i. Delay Time Remaining (Delay specified in seconds).
ii. Time Remaining Until Drift Measurement Can be Made (Delay specified in mV/s).
Alternatively, measured drift rate if measurement has taken place.
iii. Stopped Scan.