Danfoss AKS 41 Liquid Level Transmitter
Section 9
Publication 9-45
Issue 1 : 10/11
Page 15 of 18
11.
Appendix 1 AKS 41 Early Version
The early version of the AKS 41 is provided with two LEDs: one green,
one red. Pins are provided for measuring the 4 to 20 mA output signal
and for measuring a test voltage used for troubleshooting. Also, the
method of setting and calibration differs somewhat from the latter version.
G
REEN
LED
R
ED
LED
F
UNCTION
S
TATUS
O
UTPUT
S
IGNAL
4
TO
20
M
A
‘Flashing’
Off
Normal operation
Depends on liquid level
1
See note
‘Flashing’
Setting refrigerant
4, 5, 6, 7 or 8 mA (depends on
refrigerant selected)
Off
Setting signal damping
Depends on liquid level
Off
‘Flashing’
Calibrating output signal
4 to 20 mA in 2 mA steps
‘Flashing’
On
Level more than 10 %
outside measured range
4 mA if below measured range
20 mA if above measured range
1
As long as the programming button is not activated, the green LED ‘flashes’. When the programming button is activated,
the green LED follows the activation, i.e. the green LED is On whenever the programming button is pressed.
Fig 7 AKS 41 (Early Version) Internal Layout of Transmitter Housing and LED Function
11.1.
Measuring Test Voltage
Connect a voltmeter to the pins provided to measure a voltage which is
an expression of the ‘raw’ output signal measured directly from the
capacitive rod.
Two voltages are recorded during manufacture and recorded inside the
transmitter housing.
Voltage (x) at 0 %, i.e. when the rod is completely out of the liquid.
Voltage (y) at 100 %, i.e. when the rod is completely immersed in
the liquid.
In a trouble-shooting situation, by measuring the voltage between the
pins it is possible to determine whether the rod is defective. If the
measured voltage is within the two recorded values, the capacitive rod
(outer tube, insulation, electrode and wiring connections) are in order.
Green
LED
Red
LED
Two pins for
calibration of 4 to
20 mA signal
Programming
button (at
bottom of tube)
Two pins for measuring test voltage
