KEYENCE LK-2000 Series - Manual (Page 13)

13
AUTO ZERO function
Resets the output voltage to 0 V at the desired point within the measur-
ing range.
Changing the zero position enables the output range to be set at either
-10 to 0 V, or 0 to 10 V.
Canceling AUTO ZERO:
Press the ZERO RESET key for approximately 2 seconds. AUTO ZERO
is canceled and 0 V (12 mA) is output when the target is at the reference
position.
External input:
Connecting the AUTO ZERO input terminal to the GND terminal sets the
AUTO ZERO input.
Relationship between the key-lock function and AUTO
ZERO function
➮ Refer to p. 16 for the key-lock function.
When FREE is set:
The value of the AUTO ZERO input is internally stored and retained
even the power is turned off.
When LOCK is set:
The AUTO ZERO input is available only from the external input terminal.
When the power is turned off, the value of the AUTO ZERO input is not
stored, and the zero point is reset to the reference position.
Note: If the AUTO ZERO input is used frequently, set the key-lock
function to LOCK, and set the AUTO ZERO externally.
AUTO ZERO position and output characteristics
Data in ( )* applies to the LK-081.
Data in ( )** applies to the LK-501/503 in long-range mode.
Note: When the AUTO ZERO input is set immediately after the power is
turned on, there may be a 10 mV error due to the temperature character-
istics of the internal circuit. The error is gradually reduced and becomes
0 V in approximately 30 minutes.
The temperature characteristics may cause low accuracy of the AUTO
ZERO reset depending on the ambient temperature.
LK-031
25 mm
LK-031
25 mm ZERO
RESET
(4 mA) (12 mA)
V V 10
5
0
-5
25
(65)*
(250)**
(500)** (700)**
30
(80)*
35
(95)*
-10
Output voltage (v)
Distance (mm)
When AUTO
ZERO is
set at 35 mm
(95 mm)
When AUTO
ZERO
is set at 25 mm
(65 mm)
Example (LK-031/036)
LK-031/036/081/086
LK-501/503 (Long-range mode) LK-501/503
(High-precision mode)
-10
0
10
350 450 250
Output voltage (v)
When AUTO
ZERO is set
at 450 mm.
When AUTO
ZERO is set
at 250 mm.
FUNCTIONS AUTO ZERO