NK TECHNOLOGIES AT 2 Series User manual

INSTRUCTIONS
1. Run the wire you are monitoring through aper-
ture.
2. Mount the sensor to a surface if needed.
3. Connect output wiring.
A. Use up to 14 AWG 75/90˚C copper wires.
B. Make sure output load does not exceed product
specifications.
C. Connect 24 VDC power supply and load in
series.
4. Select Range
A. Chose correct range by positioning the Range
switch.
AT & ATR 2, 3 & 4 SERIES
AC Current Transducers
4-20mA Output
True RMS or Average Responding
AT R 3 - 420 - 24L - FL
OUTPUT:
420 - 4-20mA
RANGE
2 - 100, 133, 200 A
3 - 375, 500, 750A
4 - 1000, 1333, 2000A
SENSOR TYPE:
AT - AC current sensor, 4-20 mA output
loop powered
Model Number KeySpecifications
Power Supply
Quick “How To” Guide
CASE STYLE
FL- Fixed core
Current Ranges Field Selectable from 0-2000A
Current Measurement range 0-2000A@600V, CAT III
Output Signal 4-20mA, Loop Powered
Output Limit 23 mA
Power Supply 24VDC nominal, 40VDC max.
Overvoltage Cat. I, Class 2 or power limited
power supply
Accuracy 1.0% FS
Measurement True RMS or Average Responding
Frequency Range ATR: 10-400 Hz
AT: 50-60 Hz, Sinusoidal
Isolation Voltage 3kV
Response Time 500 ms (to 90% of step change)
Environmental -4 to 122°F (-20 to 50°C) operating ambient
temperature.
0-95%RH, non-condensing
Pollution Degree 2
Altitude to 2000 meters
Case UL 94V-0 Flammability rated thermoplastic
Listing UL and cUL Listed
CE Certified
RoHS Compliant
Minimum Power Supply = 12 VDC + Total Loop Voltage Drop
0 250 500 750 1000
32V
22V
12V
Operating
Range
Total Loop Impedance (Ohms)
LOOP
POWER
(VDC)
POWER SUPPLY:
24L- 24VDC Loop Powered
Measurement
R - True RMS
(Blank) - Average Responding
3511 Charter Park Drive, San Jose, CA 95136
Phone: [phone] or 408-871-7510
Fax: [phone]
[email protected], www.nktechnologies.com AT/ATR 2/3/4 Series 292001301-3
Know Your Power
Other NK Technologies Products Include:
AC & DC Current Transducers
AC & DC Current Operated Switches
1φ& 3φPower Transducers
Current & Potential Transformers (CTs&PTs)
Caution! Risk of electric shock or per-
sonal injury
Safe operation can only be guaranteed if the
transducer is used for the purpose for which
it was designed and within the limits of the
technical specifications. When this symbol
is used, it means you should consult all
documentation to understand the nature of
potential hazards and the action required to
avoid them.
Caution! Risk of hazardous voltage
When operating the transducer, certain parts
may carry hazardous live voltage (e. g. pri-
mary conductor, secondary terminals). The
transducer should not be put into service if
the installation is not complete.

Run wire to be monitored through the sensing aperture.
AT and ATR Series transducers work in the same environ-
ment as motors, contactors, heaters, pull-boxes, and other
electrical enclosures. They can be mounted in any posi-
tion or hung directly on wires with a wire tie. Just leave at
least one inch distance between sensor and other magnetic
devices.
Description
Installation
Output Wiring
Range Select
AT and ATR Series transducers feature field selectable
ranges. The ranges are factory calibrated, eliminating
time consuming and inaccurate field setting of zero or
span.
Trouble Shooting
AT and ATR Series transducers combine a current trans-
former and a signal conditioner into a single package.
This provides higher accuracy, lower wiring costs, easier
installation and save valuable panel space. AT Series are
available in solid core with 4-20mA outputs.
ATR Series feature a True RMS output. They are de-
signed for application on distorted current waveforms
such as VFD outputs.
1. Determine the normal operating amperage of your
monitored circuit
2. Select the range that is equal to or slightly higher than
the normal operating amperage.
3. Move the three position range selector switch to the
appropriate position.
1. Sensor has no output
A. Power supply is not properly sized Check power
supply voltage and current rating.
B. Polarity is reversed. Check and correct wiring polar-
ity.
2. Output Signal Too Low
A. The jumper may be set in a range that is too high for
current being monitored. Move jumper to the correct
range.
B. The load current is not sinusoidal. Select an ATR
transducer for use with distorted waveforms.
C. Monitored current is below minimum required. Loop
the monitored wire several times through the aperture
until the “sensed” current rises above minimum.
Sensed Amps = (Actual Amps) x (Number of Loops).
Count loops on the inside of the aperture.
3. Sensor is always at 4mA
A. Monitored load is not AC or is not on. Check that
the monitored load is AC and that it is actually on.
4. Output Signal is always at 20mA
A. The jumper may be set in a range that is too low for
current being monitored. Move jumper to the correct
range.
Input
Range
Output
+
–
750A
500A
375A
Input
Range
Output
+
–
750A
500A
375A
Load
(controller,
meter
etc.)
AT/ATR Transducer
(loop powered)
AT/ATR Transducer
(loop powered)
Load
(controller,
meter
etc.)
+
+
–
–
H
N
G
To
AC
Power
+
–
To Other Transducers
Power Supply
Connect control or monitoring wires to the sensor. Use
up to 14 AWG 75/90˚C copper wire and tighten terminals
to 4.4 inch-pounds torque. Be sure the output load does
not exceed 800 ohms.
Connection Notes:
• Captive screw terminals.
•14-22 AWG 75/90˚C solid or stranded.
•Observe Polarity
•See label for ranges & jumper positions
2(+)1(–)
Output
Range Switch
MidLow High
(+)(–)
24 VDC Power
(+)
(–)
Load
(Controller,
Meter, etc.)
Input Maximums
----------MAXIMUM AMPS------------
MODEL RANGE 1 SEC 6 SEC. CONTINUOUS
AT2 All 2,500A 1,000A 500A
ATR2 All 2,500A 1,000A 500A
AT3 All 3,750A 1,500A 750A
ATR3 All 3,750A 1,500A 750A
AT4 All 10,000A 4,000A 2,000A
ATR4 All 10,000A 4,000A 2,000A