Omega MSCS, MCS User guide

MINI FIXED STATUS SWITCH
SERIES

Installation & Operation Instructions

MCS, MSCS

Phone: [phone]

Website: workaci.com

PRECAUTIONS

• This product is not intended to be used for

FIGURE 1: DIMENSIONS

Solid-Core

Life or Safety applications.

• This product is not intended for use in any
hazardous or classied locations.

1.99”
(50.48mm)

HIGH VOLTAGE

• Disconnect and lock out all power sources
before installation as severe injury or death
may result from electrical shock due to

2.51” (63.82mm)

contact with high voltage wires.

GENERAL INFORMATION

The Miniature Fixed Current Status” Switches are
designed for use in any AC current monitoring
application in which you are looking for a xed trip
point to monitor the “Go/No Go” (On/O) ”Status”

Split-Core

1.82” (46.14mm)

for a particular piece of equipment. The xed
current switches should be installed on the line side
of the power to the motor, pump, compressor or
other equipment. All of the miniature current

2.38”
(60.49mm)

switches are available in both solid and split-core
versions in a smaller enclosure style than that of the
A/CS2 and A/SCS2 Series xed current switches
rated for higher operating currents.

2.65” (67.19mm)

MOUNTING INSTRUCTIONS

Make sure that all installations are in compliance with
all national and local electrical codes. Only qualied
individuals that are familiar with codes, standards,
and proper safety procedures for high-voltage
installations should attempt installation. The current
switches will not require external power, since the
power for the current switch is induced from the conductor being monitored.

2.00” (50.80mm)

2.15” (54.49mm)

0.99”

(25.06mm)

0.99”

(25.06mm)

The A/MCS and A/MSCS Current Switches should be used on Insulated Conductors Only! The current switch
may be mounted in any position using the (2) #8 x 3/4” Tek screws and the mounting holes in the base (see
Figure 2 (p.2)). Leave a minimum distance of 1” (3 cm) between the current switch and any other magnetic
devices such as contactors and transformers.

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Automation Components, Inc.

2305 Pleasant View Road | Middleton, WI 53562
Phone: [phone] | Website: workaci.com

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FIGURE 2: MOUNTING

#8 x 3/4" Tek Screw

(Qty. 2/Unit)

WIRING INSTRUCTIONS

ACI recommends the use of a two conductor 16 to 22 AWG shielded cable or twisted pair copper wire only
for all current switch applications. A maximum wire length of less than 30 meters (98.4 feet) should be
used between the A/MCS and A/MSCS current switches and the Building Management System or
controller.

Note: When using a shielded cable, be sure to connect only (1) end of the shield to ground at the
controller.

Connecting both ends of the shield to ground may cause a ground loop. When removing the shield from
the sensor end, make sure to properly trim the shield so as to prevent any chance of shorting. The current
switch output terminals represent a solid-state switch for controlling both AC and DC loads and is not
polarity sensitive. The recommended torque to be used on the terminal block connections is 0.67 Nm or

5.93 in-lbs.. The aperture (hole) size of the current switch is 0.53” (1.35 cm) and will accept a 1 AWG
maximum wire diameter.

For applications in which the normal operating current is below the 0.20 Amps (A/MCS) or 0.55 Amps
(A/MSCS) trip point (See Figure 3 below), the conductor being monitored may be looped through the
sensor 4 times giving you a total operating current of 4X the original current.

Example: A small fan operating at 0.2A should be wrapped through the sensor 4 times to give you a total
operating current of 0.8Amps owing through the A/MCS or A/MSCS.

FIGURE 3: WIRES THROUGH SENSORS

ONE LOOP FOUR LOOPS

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Automation Components, Inc.

2305 Pleasant View Road | Middleton, WI 53562
Phone: [phone] | Website: workaci.com

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For applications in which the normal operating current is greater than 150 Amps or for conductor diame­ters larger than 0.530” (1.35 cm) in diameter, an external 5 Amp Current Transformer must be used as
shown in Figure 4 below.

Remember that the secondary of the 5A CT must be shorted together before the power may be
turned onto the monitored device.

Example: For currents up to 600 Amps (and not below 70 Amps (A/MCS-A) or 95 Amps (A/MSCS-A), where

Current Transformer (C.T.) secondary falls below 1 Amp use a 600:5 ratio C.T. as shown:

FIGURE 4: CURRENT TRANSFORMER FIGURE 5: DIGITAL CIRCUIT

Insulated

600:5 Ratio 5A C.T.

Conductor

APPLICATION EXAMPLES

See Figure 5 (p.3) and Figure 6 (p.3) for two dierent current switch applications. Figure 5 (p.3) is showing
the use of the Mini Go/No Go Current Switch as a Digital Input to your BAS/PLC Controller. Figure 6 (p.3)
shows a Mini Go/No/Go Current Switch in conjunction with a Contactor to control an exhaust fan.

Note: The ACI Mini Fixed Go/No Go Current switches(MCS & MSCS Series) are only rated at 0.5A Continuous
@ 36 VAC/VDC. These switches must use an additional Contactor if controlling motor/fans.

Wire

Nut

Digital Input #1

Building Management

System

FIGURE 6: MOTOR/FAN CONTROL

NEUTRAL

120 VOLT HOT

NEUTRAL

120 VOLT HOT

RELAY

EXHAUST FAN

MOTOR

Automation Components, Inc.

2305 Pleasant View Road | Middleton, WI 53562
Phone: [phone] | Website: workaci.com

ACI SPLIT-CORE SWITCH

24 VAC HOT

NEUTRAL

RANGE HOOD FAN

MOTOR

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TROUBLESHOOTING

ACI Model #

Resistance if switch open

Resistance if switch closed

A/MCS

Greater than 1 Meg ohms

Approximately 0.2 ohms

A/MSCS

Greater than 1 Meg ohms

Approximately 0.2 ohms

PROBLEM

Current switch didn’t activate (Test #1)

Current switch didn’t activate (Test #2)

SOLUTION(S)

Disconnect the wires from the current switch output. Measure the resistance

across the contacts with an Ohmmeter. See Standard Ordering Table (p.5) for

the actual resistance readings for an open or closed switch reading.

Verify that the current owing in the conductor being monitored is above

the xed trip point as listed in the operating specications. If the sensor is

monitoring less than the xed trip point, see Figure 3.

WARRANTY

The ACI Current Switch Series are covered by ACI’s Five (5) Year Limited Warranty, which is located in the front of
ACI’S SENSORS & TRANSMITTERS CATALOG or can be found on ACI’s website: www.workaci.com.

W.E.E.E. DIRECTIVE

At the end of their useful life the packaging and product should be disposed of via a suitable recycling
centre. Do not dispose of with household waste. Do not burn.

Automation Components, Inc.

2305 Pleasant View Road | Middleton, WI 53562

Phone: [phone] | Website: workaci.com

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PRODUCT SPECIFICATIONS

SENSOR NON-SPECIFIC INFORMATION

Monitored Current Type:

Maximum AC Voltage:

Operating Frequency Range:

Core Style:

Sensor Power:

Amperage Range:

Isolation Voltage:

Trip Point Style | Trip Point:

Contact Type:

“Status” Contact Rating:

“Status” Contact “On” Resistance | “O” Resistance:

Response Time:

Aperture Size:

Operating Temperature Range:

Operating Humidity Range:

Wiring Connections:

Wire Size:

Terminal Block Torque Rating:

Minimum Mounting Distance:

Pollution Degree:

Environmental:

STANDARD ORDERING

Model #

A/MCS

A/MSCS

Item #

117852

117853

Trip Point Type

Fixed Trip Point

Fixed Trip Point

N/O

•

•

AC Current

600 VAC

50/60 kHz

Solid-Core and Split-Core Versions available (See Ordering Grid)

Induced from the Monitored Conductor (Insulated Conductors only)

See Ordering Grid

2200 VAC

Fixed Trip Point | See Ordering Grid

Normally-Open “N/O”

0.5A @ 36 VAC/VDC

< 0.5 Ohms (tripped) | > 1 Meg Ohms (Open)

A/MCS:

< 50 mS typical |

0.53” (13.46 mm)

-22 to 140ºF (-30 to 60ºC)

0 to 95%, non-condensing

2 Position Screw Terminal Block (Not Polarity Sensitive)

16 to 22 AWG (1.31 mm to 0.33 mm) Copper Wires only

4.43 to 5.31 in-lbs. (0.5 to 0.6 Nm)

1” (2.6 cm) between current switch (Relays, Contactors, Transformers)

2

Indoor

Solid-Core•Split-Core•Amp Range

A/MSCS:

0 to 150A

0 to 150A

< 40 mS typical

Trip Point

0.20A or less

0.55A or less

Contact Rating

0.5A @ 36 VAC/VDC

0.5A @ 36 VAC/VDC

Automation Components, Inc.

2305 Pleasant View Road | Middleton, WI 53562

Phone: [phone] | Website: workaci.com

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NOTES

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Automation Components, Inc.

2305 Pleasant View Road | Middleton, WI 53562
Phone: [phone] | Website: workaci.com

Version: 8.0

I0000557

NOTES

Page 7

Automation Components, Inc.

2305 Pleasant View Road | Middleton, WI 53562
Phone: [phone] | Website: workaci.com

Version: 8.0

I0000557

Automation Components, Inc.

2305 Pleasant View Road
Middleton, WI 53562

Phone: [phone]
Website: workaci.com

Page 8

Automation Components, Inc.

2305 Pleasant View Road | Middleton, WI 53562
Phone: [phone] | Website: workaci.com

Version: 8.0

I0000557