Measurements for Fault Localisation
seca
03.04.2013/JEG
19 (24)
30-34-00-864
4 Measurements for Fault Localisation
The following section contains an overview of measurements that can be made for
specific fault localisation.
4.1 Power supply
Measurement of the power supply to the PCB indicates whether the leads from the
battery compartment and/or power pack are defective. A multimeter is used for
measurement at the measuring points B (see Appendix
)
.
4.2 Load
cell
The most effective method for establishing a defect in the load cell is to use the seca
serva diagnostic function. If this is not available, another option is to use a multimeter.
Measurement with a multimeter is however not as conclusive, so this method should
always be second choice here.
4.2.1 Testing load cells with a multimeter
The load cell is first unsoldered from the electronics and the ohmic resistance between
the different connecting wires measured using a multimeter. The following tables show
the values to be expected for the various load cells:
Measurement between
Ohmic resistance [
Ω
]
V
+
and Sig
-
(green and red)
~ 800-850
V
+
and Sig
+
(green and white)
~ 800-850
V
-
and Sig
-
(black and red)
~ 800-850
V
-
and Sig
+
(black and white)
~ 800-850
Sig
+
/Sig-/V
+
/V- and aluminum body
of load cell
> 500 M
Table 6: Load cell resistances
[334|335|382|383|384|385|833|834|835|874|875|876|877|878|769|799|780|869|899]
