24
4.2.2 Calibrating using a Millivolt Source
1.
Disconnect the power from the meter.
Remove the
front lens. Notice the the zero potentiometer is located
to the left of the display and the span potentiometer is
located to the right of the display.
Refer to
Figure 4-1
for the location of the calibration
pots.
2.
Connect the millivolt source to the MCJ Electronic Ice
Point or ice bath which in turn connects to the
thermocouple input connector P3 as shown in Figure
4-3. Connect the negative (red) thermocouple wire to
connector P3, Pin 1. Connect the positive
thermocouple wire to connector P3, Pin 2. Be sure to
observe polarity and use the correct thermocouple
wire (Type J wire for Type J meter).
Figure 4-3. Calibration with a Millivolt Source
METER
P3
P2
P1
T/C WIRE
mV SOURCE
COPPER WIRE
ICE BATH
AC
METER
P3
P2
P1
T/C WIRE
AC
mV SOURCE
COPPER WIRE
OMEGA
MCJ
OMEGA
TRP PROBE
5
S
SE
EC
CT
TIIO
ON
N 3
3 G
GE
ET
TT
TIIN
NG
G S
ST
TA
AR
RT
TE
ED
D
3
3..1
1 M
Ma
aiin
n B
Bo
oa
arrd
d P
Po
ow
we
err J
Ju
um
mp
pe
errs
s
Caution:
The meter has no power-on switch, so it will be
in operation as soon you apply power.
The meter can be configured to operate on 115 Vac or
230 Vac by the proper combination of the soldered wire
jumpers that are located on the printed circuit board. The
meter is set at the factory to be powered by the voltage
specified at the time of ordering. The same transformer is
used for either configuration, so all you need to do is to
select the jumpers as described in this section.
IIm
mp
po
orrtta
an
ntt::
These changes must be performed by a
qualified technician.
To change the Factory preset jumpers, do the following steps:
Disconnect the power from the unit before proceeding.
1. Remove the main board from the case. Refer to
Disassembly/Assembly Section 3.8.
2. Locate the solder jumpers W1, W2, and W3 (located near
the edge of the main board alongside the transformer).
3. If your power requirement is 115 Vac, solder jumpers W1
and W3 should be wired, but jumper W2 should not. If
your power requirement is 230 Vac, solder jumper W2
should be wired, but jumpers W1 and W3 should not.
24
4.2.2 Calibrating using a Millivolt Source
1.
Disconnect the power from the meter.
Remove the
front lens. Notice the the zero potentiometer is located
to the left of the display and the span potentiometer is
located to the right of the display.
Refer to
Figure 4-1
for the location of the calibration
pots.
2.
Connect the millivolt source to the MCJ Electronic Ice
Point or ice bath which in turn connects to the
thermocouple input connector P3 as shown in Figure
4-3. Connect the negative (red) thermocouple wire to
connector P3, Pin 1. Connect the positive
thermocouple wire to connector P3, Pin 2. Be sure to
observe polarity and use the correct thermocouple
wire (Type J wire for Type J meter).
Figure 4-3. Calibration with a Millivolt Source
METER
P3
P2
P1
T/C WIRE
mV SOURCE
COPPER WIRE
ICE BATH
AC
METER
P3
P2
P1
T/C WIRE
AC
mV SOURCE
COPPER WIRE
OMEGA
MCJ
OMEGA
TRP PROBE
5
S
SE
EC
CT
TIIO
ON
N 3
3 G
GE
ET
TT
TIIN
NG
G S
ST
TA
AR
RT
TE
ED
D
3
3..1
1 M
Ma
aiin
n B
Bo
oa
arrd
d P
Po
ow
we
err J
Ju
um
mp
pe
errs
s
Caution:
The meter has no power-on switch, so it will be
in operation as soon you apply power.
The meter can be configured to operate on 115 Vac or
230 Vac by the proper combination of the soldered wire
jumpers that are located on the printed circuit board. The
meter is set at the factory to be powered by the voltage
specified at the time of ordering. The same transformer is
used for either configuration, so all you need to do is to
select the jumpers as described in this section.
IIm
mp
po
orrtta
an
ntt::
These changes must be performed by a
qualified technician.
To change the Factory preset jumpers, do the following steps:
Disconnect the power from the unit before proceeding.
1. Remove the main board from the case. Refer to
Disassembly/Assembly Section 3.8.
2. Locate the solder jumpers W1, W2, and W3 (located near
the edge of the main board alongside the transformer).
3. If your power requirement is 115 Vac, solder jumpers W1
and W3 should be wired, but jumper W2 should not. If
your power requirement is 230 Vac, solder jumper W2
should be wired, but jumpers W1 and W3 should not.
