MINI ADJUSTABLE STATUS SWITCH SERIES

PRECAUTIONS

• This product is not intended to be used for Life or Safety applications.
• This product is not intended for use in any hazardous or classified locations.

HIGH VOLTAGE

• Disconnect and lock out ⚠️ all power sources before installation as severe injury or death may result from electrical shock due to contact with high voltage wires.

GENERAL INFORMATION

The Miniature Adjustable Current switches are designed for use in any AC current monitoring application in which you are looking for an adjustable current switch to monitor normal operating conditions, equipment failure or preventative maintenance scheduling for a particular piece of equipment. The adjustable current switches should be installed on the line side of the power to the motor, pump, compressor or other equipment. The adjustable current status switches can also be used to determine the run time of your equipment where you want to know when your piece of equipment runs and for how long it runs when logging the contact closures on your building management system or PLC.

MOUNTING INSTRUCTIONS

Make sure that all installations are in compliance with all national and local electrical codes. Only qualified 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.

The A/MCS-A and A/MSCS-A 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.

FIGURE 1: DIMENSIONS

Solid-Core

Dimensions: Approximately 1.99 inches (50.48 mm) in height and 2.51 inches (63.82 mm) in width, with a depth of 0.99 inches (25.06 mm).

Split-Core

Dimensions: Approximately 2.38 inches (60.49 mm) in height and 2.65 inches (67.19 mm) in width, with a depth of 0.99 inches (25.06 mm). The split-core also shows a secondary dimension of 2.00 inches (50.80 mm) and 1.82 inches (46.14 mm) for its core opening.

FIGURE 2: MOUNTING

Illustration shows the switch with two #8 x 3/4" Tek screws, indicating they are used to attach the switch via mounting holes in its base. The diagram shows the switch body and how it would be secured.

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-A and A/MSCS-A 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-A) or 0.55 Amps (A/MSCS-A) 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 flowing through the A/MCS-A or A/MSCS-A.

FIGURE 3: WIRES THROUGH SENSORS

ONE LOOP

A single pass of the conductor through the sensor aperture.

FOUR LOOPS

The conductor passing through the sensor aperture four times, which multiplies the sensed current by four.

EXTERNAL CURRENT TRANSFORMER USAGE

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 in Figure 4.

FIGURE 4: CURRENT TRANSFORMER

Diagram shows an insulated conductor passing through the center of a 600:5 Ratio 5A CT. A wire nut is shown connecting the secondary leads of the CT.

FIGURE 5: DIGITAL CIRCUIT

Diagram shows a connection from a 'Digital Input #1' of a Building Management System to the current switch output. This setup uses the switch as a digital input signal.

APPLICATION EXAMPLES

See Figure 5 (p.3) and Figure 6 (p.3) for two different 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 Adjustable Go/No Go Current switches (MCS-A & MSCS-A Series) are only rated at 1.0A Continuous @ 36 VAC/VDC. These switches must use an additional Contactor if controlling motor/fans.

FIGURE 6: MOTOR/FAN CONTROL

Diagram illustrates a Motor/Fan Control circuit. It shows a 120 Volt Hot and Neutral line connected to a relay. The ACI Split-Core Switch is shown monitoring the power to a motor. The switch output controls the relay, which in turn controls an Exhaust Fan or a Range Hood Fan. The circuit also shows a 24 VAC Hot and Neutral line for the relay coil.

CALIBRATION OF ADJUSTABLE TRIP POINT

The adjustable current switch has an operating range of 0-150 Amps. Do not exceed! The adjustable current switch comes with its fifteen-turn adjustment potentiometer set to the 100 Amp trip point position. The adjustable current switch can be used to monitor Under Load, Normal Load, and Over Load conditions, depending on how it's set. The procedure below is for the Normal load condition for part numbers A/MCS-A & A/MSCS-A.

NORMAL LOADS

With current flowing through the aperture of the A/MCS-A and A/MSCS-A current switches, first verify that the Blue LED is on. If the Blue LED is on, now slowly adjust the potentiometer clockwise until the Red LED just turns on and stop immediately. This will set the trip point at your normal operating load current.

If the RED LED is on after initial power up, this means that you will need to slowly adjust the potentiometer counter-clockwise until the Blue LED turns on and then slowly adjust the potentiometer clockwise until the Red LED just turns on and stop immediately. The adjustable current switch is now tripped. Now verify the output with an Ohmmeter to verify that the contacts of the switch are approximately 0.200 Ohms. The adjustable current switch Hysteresis (Dead Band) is typically 10% of the trip point.

• Clockwise = Decrease Trip Point
• Counter-clockwise = Increase Trip Point

TROUBLESHOOTING

Resistance Table

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.

PRODUCT SPECIFICATIONS

SENSOR NON-SPECIFIC INFORMATION

Note: The LED should not be used to determine if current is present. At low currents the LED may not be visible.

STANDARD ORDERING