NK Technologies AG1, AG2, AG3 INSTRUCTIONS

Model Number KeySpecifications

Setpoint Range AG1 Series: 5-100mA Field Adjustable

AG2 Series: 80-950mA Field Adjustable
AG3 Series: Tri-Set, 5, 10 & 30 mA,

Jumper Select

Voltage Range Up to 1,500 VAC (Monitored Circuit)
Frequency Range 50-400Hz (Monitored Circuit)
Output Options (See Product Label)

Relay Output 1.0A @ 120 VAC, 2A @ 30 VDC
Solid State AC Switch NOT COVERED
Solid State DC Switch NOT COVERED

Response Time 150 mS @ 5% above setpoint.

100 mS @ 50% above setpoint.
Power Supply Operates from 55-110% of nominal voltage
Nominal Voltages 120 VAC (50-400 Hz)

Green LED=Power
Optional Power 24VAC +/-15% or 24 VDC Operates +/- 20%
Power Consumption 2.5 Watts
Dimensions 2.5"H x 2.8"W x 1.5"D, (64x71x38mm),

aperture 0.75" (19mm) dia.
Case UL 94V-O Flammability Rated
Environmental 5 to158 DegF (-15 to 70 DegC), 0-95% RH,

Non Condensing
Listings UL 1053, Class 1 Recognized, CSA

Approved, CE Certified

AG 1-SDT1 -120-ENE -005

Setpoint

005 to 950 Factory Adjusted

TR3 Tri-Set, 5, 10 & 30

Options

ENE Normally Energized
DEN Normally De-energized

Power Supply

24U 24 VAC/DC
120 120 VAC

Output Type

SDT1 SPDT Relay (Form C)

1A @ 120 VAC, 2A @ 30 VDC

Setpoint Range

1 5-100mA, Adjustable
2 80-950mA, Adjustable
3 Tri-Set, 5, 10 & 30 mA, Jumper Select

AG Series Ground Fault Sensor

Setpoint in mA
(specify when
ordering)

mA, Jumper Select

INSTRUCTIONS

AG1, 2 & 3 SERIES

Ground Fault Sensors

with Relay Outputs, Auto-Reset

Power Supply Notes

All low-current Ground-Fault Sensors are sensitive devices
that require reasonable care in system design to avoid false
trips caused by high electrical noise levels. Keep in mind that
the best way to reduce noise in a system is to suppress it at its
source.

1. Keep the sensor power isolated from noisy circuits.

2. Do not power the sensor with the same circuit that

switches contactors or other high current, inductive loads.

System Grounding

Good design practice and code require that all AC power
systems be grounded. AG Series sensors are designed to
work on grounded AC power systems. They may not operate
properly on ungrounded systems.

Know Your Power

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)

3511 Charter Park Drive, San Jose, CA 95136
800-959-4014 or [phone] Phone
[phone] FAX
[e-mail], www.nktechnologies.com

Quick “How To” Guide

1. Run all current carrying conductors
through sensor window

A. Use an auxiliary CT if conductors do not fit. Con-

sult Factory for CT selection.

2. Mount the sensor to a surface if needed.

3. Connect output & power wiring.

A. Use up to 14 AWG copper wires.
B. Make sure power and load matches those shown on

the senors’ label.

4. Test

A. Pressing the “TEST” button tests the sensors inter-

nal circuits. CAUTION: The output and any con­nected loads will switch!

AG-Relay Inst. Rev 4- 10/10, P/N 49-010-0001

Description

Installation & Wiring

AG Series sensors monitor all current carrying wires in
single or three phase systems to detect ground faults. They
provide a contact output that can operate relays, contactors
or signal automation systems.

Principal of Operation

Under normal conditions, the current in one wire of a two
wire load is equal in strength but opposite in sign to the
current in the other wire. The two wires create magnetic
fields that cancel, a condition known as “Zero Sum Cur­rent”. If any current leaks to ground (Ground Fault), the
two currents become unbalanced and there is a net resulting
magnetic field. The AG sensor detects this minute field and
changes the output state. This concept extends to three
phase systems such as 3 wire Delta and to 4 wire Wye.

1 Power

1 Load

Power

3 Power

1 Load

Power

HOT

NEUT

Power

Power

A

B

Output

AG Series

Output

AG Series

Interupt

Interupt

AG Series sensors work in the same environment as mo­tors, contactors, heaters, pull-boxes, and other electrical en­closures. They can be mounted in any position or hung
directly on wires with a wire tie. Just leave at least one inch
distance between sensor and other magnetic devices.

Run all current carrying conductors through the sensor
apeture in the same direction. (See “Principal of Opera­tion”)

Connect power wiring to the sensor. Be sure that the power
supply matches the power rating on the sensor label. Use
up to 14 AWG copper wire and tighten terminals to 7 inch­pounds torque.

Operation

To test operation, gently press the
TEST button. This simulates a
fault and tests the internal switch­ing circuits.You should observe
the following operation.

CAUTION: Any circuit con­nected to the sensor will be op­erated.

Normally Energized Models (-ENE) Detects Ground Faults and loss of control power

Output Output LED Output LED Output LED

N.C. Normally Closed CLOSED Off OPEN OFF CLOSED ON
N.O. Normally Open OPEN Off CLOSED OFF OPEN ON

Normally De-Energized Models (-DEN) Detects Ground Faults only.

Output Output LED Output LED Output LED

N.C. Normally Closed CLOSED Off CLOSED OFF OPEN ON
N.O. Normally Open OPEN Off OPEN OFF CLOSED ON

Connect output wiring to the sensor. Be sure that the out­put load is less than or equal to than the output rating on
the sensor label. Use up to 14 AWG copper wire and tighten
terminals to 7 inch-pounds torque.

TEST

Load

Output Power

Match Sensor Rating

(See Label)

Setpoint Adjust

(AG1&2) Factory calibrated
& covered. Remove cover,
adjust & relabel if required.

AG3 Move jumper to select
setpoint.

Control Power

Match Sensor Rating

(See Label)

1

2 3

Power

G X

R

Status

Power

Contactor, Relay, Shunt Trip Breaker, etc.

Do not exceed Rating (See Label)

5

4

Output

CONTROL POWER APPLIED

NO POWER No Fault Fault Detected

CONTROL POWER APPLIED

NO POWER No Fault Fault Detected

3 Delta Power

Power

A
B
C

Power

A
B
C
N

Output

AG Series

Output

AG Series

Power

Interupt

Power

Interupt

3 Load

3 Wye Power

3 Load

Setpoint Adjustment

AG1 & AG2 Series sensors are factory calibrated to trip at
the setpoint specified at the time order. We highly recom­mend leaving this factory calibrated setpoint alone. If you
must change the factory setpoint, follow these steps:
A. Setup
Connect control power and output circuits. Run a conductor
through the aperture with current equal to your desired set
point .
B. Adjust Setpoint to Maximum
Remove the Setpoint Cover. Turn the adjustment pot 5
revolutions CCW (Counter Clockwise) to the maximum

The adjustment pot has a slip clutch so you cannot feel or
damage the end point.
C. Dial in new Setpoint
Turn the pot slowly CW (Clockwise) until the LED turns
ON. The sensor is now adjusted to trip at the current that is
passing through the aperture. Reset the sensor.
D. Relabel Sensor
Relabel the sensor with the new setpoint. Use a label maker
or tape with a permanent marker.
AG3 Move the jumper to the desired setpoint as shown on
the label.

(least sensitive) setpoint. The Status LED should be OFF.