Fluke A40B, Instruction Manual

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A40B
Instruction Manual
12
Table 3. Features and Connectors
Item Feature Description
A
Current Input Connector Connector for applying current to the shunt. All of the
shunts use the N-type female connectors except the 50 A
and 100 A versions which use type LC female Connectors.
B
Voltage Output Connector Connector for measuring voltage drop across the shunt.
The output connectors are all N-type female.
C
Guard Connection Binding post terminal for making a guard connection to
Shunt Lo.
D
PCB Struts Low inductance connections carrying current to and from
the shunt resistors.
E
Power on/off switch Switches power for the current Shunt on or off.
F
LED indicators Green indicates power on. Red indicates low battery.
G
Battery charger connector Input connector for the external battery charger.
Input/Output Connectors
XW
Warning
To avoid skin burns and possible damage to the 50 A and 100 A
Current Shunts, make sure the current-carrying input
connectors are undamaged and fully tightened before applying
current to them.
The input connectors on the 50 A and 100 A shunts are of the LC-type. Under full current
conditions, the connectors will get hot to the touch. This is normal because of contact
resistance. If the connectors are not fully tightened, they will get hot enough to burn skin
and damage the shunt.
W Caution
To avoid pin damage to N-Type connectors on the Current
Shunts, make sure the male pin of a mating connector is in
tolerance and does not protrude.
All other coaxial connectors on the Current Shunts are 50
Ω
, female, N-type. These
connectors are especially vulnerable to damage while being connected to a male N-type
connector. If the male connector is out-of-tolerance or its center pin protrudes too far, it
will splay the center pin of the female connector and lead to a poor connection. If there is
any doubt about the condition of the center pin in a female N-type connector, gauge the
connector (see MIL-C-39012 for details).
In extreme cases of connector damage, the connection resistance may be high enough to
prevent some current sources from driving the additional compliance voltage, particularly
at higher frequencies.
Another potential compliance voltage problem occurs when a Current Shunt is in series
with an inductance. The inductance can also burden current sources beyond their
capability. To help counter the effect, make sure the current connections are coaxial and
as short as possible.
A defective connector on a Current Shunt is replaceable. However, Fluke recommends
the work be done at a Fluke Service Center.