ACI A/ASCS2-L Adjustable Trip Point Current Switch
An adjustable current switch lets the installer set the trip threshold in the field, which is what makes it suitable for condition monitoring rather than simple on/off proof. Because the A/ASCS2-L trip point can be placed between the loaded and unloaded current of a driven load, it can distinguish a motor that is running normally from one that is running but has lost its belt, is slipping, has a locked rotor, or is otherwise running under- or over-loaded. ACI lists overload, underload, broken belt, belt slippage, locked rotor and equipment failure as the supported applications for adjustable current switches.
The split-core housing opens around an existing conductor, so the A/ASCS2-L can be fitted to wiring that is already terminated. ACI directs that the switch be installed on the line side of the power feeding the monitored equipment, and that all power sources be disconnected and locked out before the device is installed. That is what makes split-core the standard choice for retrofit work and for service vehicles, where one part covers most jobs.
Power for the switch is induced from the monitored conductor itself, so there is no 24 VAC or 24 VDC supply to run and no transformer to size. The unit ships with ACI's patented 35 mm DIN rail mounting foot (U.S. Patent No. 7,416,421) for panel installation.
Specifications on this page are taken from the ACI Adjustable Switches data sheet (ACS2, ACSX2, ASCS2 & ASCSX2 Series) and Installation & Operation Instructions I0000788 Rev. 12.0.
Best For
- Belt-loss, belt-slip and locked-rotor detection where the trip point must sit between loaded and unloaded current
- Preventative maintenance scheduling driven by measured load change
- Motor, pump, fan and compressor run status feedback to a BMS, PLC or DDC controller
- Proof-of-operation and run-status interlocks on air handlers and hydronic equipment
- Runtime accumulation and basic load trending from dry-contact closures
- Lighting circuit status and usage logging
Warranty
Key Features
Field-Adjustable Trip Point
Trip threshold is set in the field anywhere from 0.6 to 180 A, with 10% hysteresis typical, so the switch can be tuned to the actual load rather than a factory default.
Self-Powered by Induction
Power is induced from the monitored conductor. There is no 24 V supply to run, no transformer to size and no separate power wiring to install.
Split-Core Aperture
Opens around an existing conductor for retrofit installation without disconnecting any wiring.
Normally-Open (N/O) Dry Contact
Rated 0.2 A @ 200 VAC/VDC, wired to a 2-position screw terminal block that is not polarity sensitive. Contact resistance is under 10 Ohms tripped and over 1 Meg Ohm open.
Patented DIN Rail Mounting Foot
Snaps directly onto 35 mm DIN rail or mounts with two #8 Tek screws, in any orientation. U.S. Patent No. 7,416,421.
Two-Colour Status LED
Red indicates current above the trip point, blue indicates current below it, which makes setting the threshold a visual operation.
Technical Specifications
| ACI Item Number | 142352 |
| Core Style | Split-Core |
| Trip Point Style | Adjustable Trip Point |
| Trip Point | 0.6 to 180 A |
| Amperage Range | 0 to 250 A |
| Contact Type | Normally-Open (N/O) |
| Contact Rating | 0.2 A @ 200 VAC/VDC |
| Hysteresis | 10% of trip point, typical |
| Operating Frequency Range | 40 Hz to 1 kHz |
| Status LED Indication | Red LED (current above trip point) | Blue LED (current below trip point) |
| Monitored Current Type | AC Current |
| Maximum AC Voltage | 600 VAC |
| Sensor Power | Induced from the monitored conductor |
| Isolation Voltage | 2200 VAC |
| Contact On Resistance | Off Resistance | < 10 Ohms (tripped) | > 1 Meg Ohm (open) |
| Aperture Size | 0.75 in (19.05 mm) |
| DIN Rail Size | 35 mm (U.S. Patent No. 7,416,421) |
| Operating Temperature Range | 5 to 104 °F (-15 to 40 °C) |
| Operating Humidity Range | 0 to 95% RH, non-condensing |
| Recommended Storage Temperature | RH | 41 to 95 °F (5 to 35 °C) | 40 to 85% RH, non-condensing |
| Enclosure Material | Flammability Rating | PC/ABS (polycarbonate / ABS blend) | UL94-V0 |
| Wiring Connections | 2-position screw terminal block (not polarity sensitive) |
| Wire Size | 16 to 22 AWG (1.31 mm2 to 0.33 mm2), copper wires only |
| Terminal Block Torque Rating | 4.43 to 5.31 in-lbs (0.5 to 0.6 Nm) |
| Minimum Mounting Distance | 1 in (2.6 cm) from relays, contactors and transformers |
| Agency Approvals | UL/CUL US Listed (UL 508) Industrial Control Equipment, File # E309723, CE, RoHS2, WEEE, UKCA |
| Product Dimensions (L x W x H) | 2.780 in (70.51 mm) x 3.238 in (82.25 mm) x 1.120 in (28.45 mm) |
| Product Weight | 0.280 lbs (0.127 kg) |
| Warranty | Five (5) Year Limited Warranty |
Not intended for use in life / safety applications or in hazardous / classified locations.
Response Time
| Current Above Trip Point | Response Time |
|---|---|
| 0.60 A | 400 mS |
| 0.75 A | 270 mS |
| 1.0 A | 183 mS |
| 10 A | 62 mS |
| 20 A | 60 mS |
Documentation
ACI Adjustable Switches Data Sheet (ACS2, ACSX2, ASCS2 & ASCSX2 Series)ACI Adjustable Switches Series Installation & Operation Instructions (I0000788 Rev. 12.0)Related Products
Frequently Asked Questions
What is the trip point of the ACI A/ASCS2-L?
The A/ASCS2-L trip point is 0.6 to 180 A. It is adjustable in the field over that range, with 10% hysteresis typical.
Does the ACI A/ASCS2-L need external power?
No. Power is induced from the conductor being monitored, so no 24 VAC or 24 VDC supply, transformer or power wiring is required. The two terminals carry the dry contact output only.
Is the ACI A/ASCS2-L solid-core or split-core?
The A/ASCS2-L is split-core. Split-core units open around an existing conductor and install without disconnecting any wiring, which is why they are used in retrofit work.
What is the contact rating of the ACI A/ASCS2-L?
The status contact is Normally-Open (N/O) rated 0.2 A @ 200 VAC/VDC. Contact resistance is under 10 Ohms when tripped and over 1 Meg Ohm when open.
What amperage range does the ACI A/ASCS2-L monitor?
The A/ASCS2-L monitors 0 to 250 A with a maximum conductor voltage of 600 VAC and 2200 VAC isolation.
ACI Five (5) Year Limited Warranty. This product is covered by Automation Components, Inc.’s Five (5) Year Limited Warranty, published in the front of the ACI Sensors & Transmitters catalog and on the ACI website. Warranty terms are set by the manufacturer and are subject to change without notice.
- Mounting Type:
- Split-Core
- Setpoint:
- Adjustable Trip
- Contact Type:
- Normally Open
- Amp Range:
- 0-250A
- Trip Point:
- 0.6-180A
- Contact Rating:
- 0.2 A @ 200 VAC/VDC
- Contact Termination:
- Terminal Strip
- Sensor Power:
- Self-Powered
- Warranty:
- 5-Year Limited
