BusWorks® 961/962EN User’s Manual Modbus TCP/IP Differential I/V Input
___________________________________________________________________
_______________________________________________________________________________________
Acromag, Inc. Tel:248-624-1541 Fax:248-624-9234 Email:
sales@acromag.com
http://www.acromag.com
35
AC Current Sensor (Model 5020-350, For Use With 961EN):
This
sensor is a toroidal instrument transformer that converts a sinusoidal
50-60Hz AC current signal into a low level DC milliampere signal of 0 to
11.17mA. The input AC current range is a function of the number of
turns placed through the toroid as shown in Table 1 below. This sensor
is isolated and requires no calibration or adjustment. When used with a
961EN module, it provides redundant input isolation and may facilitate
input-to-input isolation of this six channel unit.
Table 1: AC Current Sensor Turns & Range
AC Current
Input Range
Primary Turns
Sensor Output
(Red/Black Wires)
0 to 20A AC
1
0 to 11.17mA DC
0 to 10A AC
2
“
0 to 5A AC
4
“
0 to 2A AC
10
“
0 to 1A AC
20
“
The output wires of this sensor are polarized with red as (+) plus and
black as (-) minus. Normally these output wires are attached to one
end of a user supplied cable while the other end connects to the
961EN’s process current input terminals.
Input Burden
: A function of the wire gauge resistance used for primary
turns (the current carrying wire being monitored).
AC Current Sensor to Transmitter Wiring Distance
: 400 feet
maximum for 18 gauge wire. Other wire gauges can be used as long
as the resistance of both wires is less than 5
Ω
.
Input Overload
: The AC current sensor will withstand overload
conditions as follows:
•
20 times full scale for 0.01 seconds.
•
10 times full scale for 0.1 seconds.
•
5 times full scale for 1.0 second.
DC Voltage (962EN Only):
A 10:1 input divider is installed at the input
(utilizing divider resistor values of 100K and 10.5K). User-configurable
for the nominal bipolar DC voltage ranges of
±
10V,
±
5V,
±
2.5V,
±
1.25V,
±
625mV,
±
313mV,
±
156mV, and
±
78mV DC.
Input Impedance:
110.5K
Ω
.
Voltage Input Reference Test Conditions:
-10 to 10V DC input;
ambient temperature = 25
°
C; 24VDC supply.
Input Overvoltage Protection:
Bipolar Transient Voltage Suppressers
(TVS), 18V clamp level typical.
Accuracy:
Better than
±
0.05% of span, typical for nominal input ranges
(except 0-1mA). This includes the effects of repeatability, terminal
point conformity, and linearization, but does not include sensor
error.
Measurement Temperature Drift:
Better than
±
50ppm/
°
C
(±0.005%/
°
C).
Analog to Digital Converter (A/D):
A
16-bit
Σ
-
∆
converter.
Resolution:
0.005% or 1 part in 20000 (961EN), 0.0025% or 1 part in
40000 (962EN, full bipolar range).
SPECIFICATIONS
Analog Inputs
General Specifications
