ABB SM1000, User Manual

Page: 102 / 134

Videographic Recorder
SM1000 5 Installation
100 IM/SM1000 Issue 11
5.4 Analog Inputs
5.4.1 Current and Voltage – Fig. 5.6
5.4.2 Thermocouple – Fig. 5.6
Use the correct compensating cable between the thermocouple
and the terminals – see Table 5.1 on page 102.
Automatic cold junction compensation (ACJC) is incorporated
but an independent cold (reference) junction may be used.
5.4.3 Resistance Thermometer (RTD) – Fig. 5.6
On applications requiring long leads it is preferable to use a 3-
lead resistance thermometer.
If 2-lead resistance thermometers are used, each input must be
calibrated to take account of the lead resistance.
5.4.4 Transmitter Power Supply – Fig. 5.7
Warning.
„
When input 'Type' is set to 'Volts' (see Section 4.6.2,
page 74), input signals with voltages greater than 2V
(standard inputs) or 1V (high specification inputs)
must
be connected through an external voltage divider (part
no. GR2000/0375).
„
Input signals with voltages up to 2V (2000mV –
standard inputs) or 1V (1000mV – high specification
inputs) may be measured without the need for the
voltage divider by setting 'Type' to 'millivolts' – see
Section 4.6.2, page 74.
„
An external 10
Ω
shunt resistor is required for current
ranges.
„
To avoid damage to multi-channel instruments, high
common mode voltages up to 500V r.m.s. max. must
be present on all channels, or not at all.
„
For the standard input card the maximum channel-to-
channel voltage (between any two channels) must not
exceed 35V or permanent damage to the instrument's
input circuitry may occur. For applications requiring
higher levels of isolation refer to the high specification
card.
Note. Two 24V power supplies are provided on the
transmitter power supply module boards, each of which is
capable of driving two 2-wire transmitters.
Fig. 5.6 Analog Input Connections
Warning. Under no circumstances must the spare input
terminal be linked to the negative.
Note. Refer also to Fig. 5.5 for terminal numbers.
Fig. 5.7 Transmitter Power Supply
Voltage divider
(GR2000/0375)
required for
voltage inputs –
see Warnings
A – Voltage
10 W Resistor supplied
in accessory pack.
B – Current C – Thermocouple
Each lead must be of equal
resistance and less than 10 W
D – 3-lead RTD
E – 2-lead RTD
(and resistance)
+
–
3rd Lead
White
Red
Red
+
–
White
Red
Sleeved
Link
+
–
3rd Lead
F – Volt Free Digital Input (Standard Inputs)
Logic state
inactive
Logic state
active
+
–
+
–
G – Volt Free Digital Input (High Specification Inputs)
Logic state
inactive
Logic state
active
Sleeved
Link
+
–
+
–
+
–
2-wire Transmitter Power Supply
(24V DC, 45mA max.)
Analog Input
10 W Shunt
Tx