Omega CN3440 - Manual (Page 14)

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4.6 Input Connections
Make connections to each input, as shown in Figs 4.4 to 4.14, first removing any factory-fitted
wire links not required.
4.6.1 Thermocouple (THC) Inputs – Fig. 4.7
Note. Automatic Cold Junction Compensation (ACJC) is active when an input is
programmed for use with thermocouples. Use the correct compensating cable between the
THC and the terminals – see Table 4.2.
If an external fixed cold junction is used, the connections to the instrument must be made
with copper cable. The input must be programmed for mV input signals and the appropriate
THC linearizer selected – see Sections 4.5 and 4.6 of the
Programming Guide.
Table 4.2 Thermocouple Compensating Cables
4.6.2 3-lead Resistance Thermometer (RTD) Inputs – Fig. 4.8
The three leads must have equal resistance, not exceeding 50
Ω each.
4.6.3 2-lead Resistance Thermometer (RTD) Inputs – Fig. 4.9
If long leads are necessary it is preferable to use a 3-lead RTD. If the RTD is to be used in a
hazardous area a 3-lead RTD must be used.
4.6.4 Links for Unused Inputs
To reduce susceptibility to electro-magnetic interference, ensure that the three terminals on
each unused input are shorted together with sleeved wire links.
…4 ELECTRICAL INSTALLATION
f o e p y T
e l p u o c o m r e h T
e l b a C g n i t a s n e p m o C
3 4 8 1 S B
I S N A
1 . 6 9 C M
N I D
4 1 7 3 4
7 3 9 4 S B
0 3 . o N t r a P
) K ( l A - i N / r C - i N
n w o r B +
e u l B –
d e R e s a C
w o ll e Y +
d e R –
w o ll e Y e s a C
d e R +
n e e r G –
n e e r G e s a C
n e e r G +
e t i h W –
* n e e r G e s a C
) N ( li s i N / li s i r c i N
e g n a r O +
e u l B –
e g n a r O e s a C
e g n a r O +
d e R –
e g n a r O e s a C
—
k n i P +
e t i h W –
* k n i P e s a C
) S d n a R ( h R - t P / t P
e t i h W +
e u l B –
n e e r G e s a C
k c a l B +
d e R –
n e e r G e s a C
d e R +
e t i h W –
e t i h W e s a C
e g n a r O +
e t i h W –
* e g n a r O e s a C
) T ( i N - u C / u C
e t i h W +
e u l B –
e u l B e s a C
e u l B +
d e R –
e u l B e s a C
d e R +
n w o r B –
n w o r B e s a C
n w o r B +
e t i h W –
* n w o r B e s a C
) J ( n o C / e F
w o ll e Y +
e u l B –
k c a l B e s a C
e t i h W +
d e R –
k c a l B e s a C
d e R +
e u l B –
e u l B e s a C
k c a l B +
e t i h W –
* k c a l B e s a C
s t i u c r i c e f a s y ll a c i s n i r t n i r o f e u l B e s a C *
) 0 1 7 3 4 N I D ( n o C / e F — —
0 1 7 3 4 N I D
d e r / e u l B +
e u l B –
e u l B e s a C
—