Metrohm E1620, Инструкция по эксплуатации

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(5) Connect the standard Kelvin lead set into the E1620.
One pair of leads should be connected into the C1 and
P1 sockets, and the other into the C2 and P2 sockets as
illustrated below in Fig. 2. Connect the two Kelvin
crocodile clips to a shorting bar.
Fig. 2
(6) Switch on the instrument by pressing the test switch
and holding it depressed.
(7) The low current warning lamp ‘I’ should not light and
the LCD should indicate zero within a digit.
(8) If the negative sign appears on the LCD, as shown in
Fig. 3, this indicates that the potential leads are reversed
in relation to the current leads. This is rectified by
reversing the potential leads to the sockets P1 and P2
Current Leads
1. Shrouded, 4mm, safety plugs are
required at one end of each lead as
before.
2. Insulated, 16/0.2mm, tinned copper
wire is recommended.
3. The length of these two leads should
be chosen so that the overall lead
resistance is less than 1
Ω
.
Fig. 4
5.6 Thermal Effects
Temperature can have a significant effect on the performance of
this instrument due to the temperature coefficient of resistance
and thermal EMFs across connections of dissimilar conductors.
Most conductors have a large temperature coefficient of
resistance, e.g. 0.4%/ºC for copper. As an example, a copper
conductor that has a resistance of 10.00m
Ω
at 20ºC will increase
Current Leads
1. Shrouded, 4mm, safety plugs are
required at one end of each lead as
before.
2. Insulated, 16/0.2mm, tinned copper
wire is recommended.
3. The length of these two leads should
be chosen so that the overall lead
resistance is less than 1
Ω
.
Fig. 4
5.6 Thermal Effects
Temperature can have a significant effect on the performance of
this instrument due to the temperature coefficient of resistance
and thermal EMFs across connections of dissimilar conductors.
Most conductors have a large temperature coefficient of
resistance, e.g. 0.4%/ºC for copper. As an example, a copper
conductor that has a resistance of 10.00m
Ω
at 20ºC will increase
(5) Connect the standard Kelvin lead set into the E1620.
One pair of leads should be connected into the C1 and
P1 sockets, and the other into the C2 and P2 sockets as
illustrated below in Fig. 2. Connect the two Kelvin
crocodile clips to a shorting bar.
Fig. 2
(6) Switch on the instrument by pressing the test switch
and holding it depressed.
(7) The low current warning lamp ‘I’ should not light and
the LCD should indicate zero within a digit.
(8) If the negative sign appears on the LCD, as shown in
Fig. 3, this indicates that the potential leads are reversed
in relation to the current leads. This is rectified by
reversing the potential leads to the sockets P1 and P2
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