Weller WA2000 - Manual (Page 4)

2005 Cooper Industries, Inc. 3 S805
3/05
TIP VOLTAGE POTENTIAL
Tip to ground noise is typically associated with any electrical voltage that is induced
by the iron itself and can be measured from the working area of the tip referenced to
ground. The DOD requirements are quite clear as to the maximum RMS voltage that
should not be exceeded.
To measure this low level voltage accurately, it should be tested under "ideal"
conditions, i.e., an electrically shielded screen room. This helps to eliminate spurious
noise generated from sources other than the iron itself.
MEASUREMENT PROCEDURE
1. Set the analyzer rotary selector switch to the mVAC position.
2. Plug the iron under test into the ground adapter and plug the adapter into an AC
source. Connect the ground lead from the adapter into the analyzer GND
receptacle and plug a pyrometer into the TEST receptacle (Do not use the K-111
or K-181 thermocouple assembly for this test).
3. With the iron under test off, contact the pyrometer with the iron's tip. The iron
"holder" provided with the WA2000 may be used to hold the iron steady. Record
the analyzer reading V
1
.
4. Turn iron under test on and allow to stabilize. With the iron's tip making contact to
the pyrometer, add additional solder to the tip to increase contact area. Allow to
stabilize for thirty seconds. Record the analyzer reading V
2
.
5. Calculate tip noise V
TIP
= V
2
- V
1
. This procedure removes extraneous noise,
which is measured with the iron off. Remember, per the MIL-STD-2000
procedure, for adjustable temperature controlled irons, measurements are to be
taken at the maximum temperature setting. For fixed temperature irons,
measurements will be taken at its rated temperature.
TIP TO GROUND RESISTANCE
The WA2000 is capable of measuring tip to ground resistance up to 100.0 ohms. Per
the MIL-STD-2000 specification, an iron's tip to ground resistance must not exceed two
ohms. This measurement must be made with the iron hot. There is no need to be
concerned with polarity (Seebeck induced errors) since the patented circuit design
removes the error electronically which provides an accurate, corrected reading in ohms.