Electronic Current-Transducer Type STWA1AH

The STWA1 current transformer is made to match the STW current monitor. One current transformer is required for each line being monitored. The STWA1 consists of a climate-proven sealed-in coil with toroidal tape core. The connection cables are permanently fixed to the transformer and are 1 m in length. The level of the current to be monitored is limited to 100 A continously, 300 A for max. 10s.In case of current of more than approx. 5 A, an LED can be triggered directly via the STWA 1 current transformer. Thus it's easy for users to visually monitor the current conduction in a line. The LED is protected by an anti-parallel diode or by its connection in series. A protective resistor is necessary depending on the LED used or the level of current being monitored.Weight: approx. 43 g

The STWA1FH provides a frequency output with 0.5...20 Hz which corresponds to a current flow of AC 0 - 20 A through the trans­former. Multiple loops of the conductor through the transformer reduce the current range corres­pondingly (e.g. with fourfold looping-through 0 - 5 A correspond to 0.5...20 Hz).For the monitoring of high currents, the STWA1FH is simply looped in the secondary circuit of a large current transformer. Consequently, the frequency output is proportional to the primary current of the transformer, e.g. 0 - 100 A for a transformer with 100/5 A (cable four times through the STWA1F).The offset of 0.5 Hz at the beginning of the transducing range is for tech­nical reasons. During evaluation, it can be taken into account.Application: The STWA1FH enables moderately priced detection of the value of an AC-current with a DIGITAL INPUT of a PLC. Costly analogue inputs are no longer necessary.The STWA1FH is particularly suitable to evaluate the current in electric motors in machines of i.e. saws. The  feed can be regulated dependent from the load of the motor of the saw. Overview of Functionscurrent-proportional frequency output 0.5 - 20 Hz =   AC 0 - 20 Aoutput isolated, max DC 30 V/30 mAoutput frequency limited to 30 Hzoutput can be connected to the digital input of a PLCincorporated reverse voltage protection diodeelectrical connection via screwless pluggable terminalssupply voltage DC 10...30 VDIN-rail-mount or with screwsplug-in current transformer (Ø 11 mm)option: currents up to 60 A, other frequencies

The STWA1H current transformer is made to match the current-relays for recognition of AC-current and for controls for deducting plants type STW. Above app. 2 A the built-in LED lights and indicates a current. A current-relay type STW or a LED can be connected to the terminals.The STWA1H has been designed for mounting in a switchgear cabinet. The housing can be fixed on a DIN-rail or with 2 screws. The maximum diameter of the monitored line is 11 mm. The current is only limited by the diameter that can be lead through the transformer. The electrical connection is made via screwless pluggable terminals.connection to current-relays type STWindication with LED from app. 2 Aindication of shortest current-pulsesBuilt-in resistor to protect LEDno supply-voltage requiredelectrical connection via screwless pluggable terminalsplug-in current transformer (Ø 11 mm)

The electronic current transformer STWA1LH monitors alternating currents 2 ... 20 A. For lower currents, the monitored wire can be led multiple times through the transformer. Used in the secondary circuit of transformers (e.g. 100/5 A), it is possible to monitor higher currents. The STWA1LH directly switches alternating voltage up to AC 230 V / 0,35 A.Control of ventilations or suction plantsControl of valves at suction plants in the woodworking industryFeatures Monitoring of alternating current up to 20 AResponse value adjustable 2 ... 20 ATwo-wire contact (voltage supply through output)Operating voltage AC 24 ... 230 VTransformer, ø 11 mmSpace-saving, easy mountingPotential separation between monitored current circuit and switch output

The STWA1S has an integrated electronic with transistor-output. The switching point is 2 A. Above app. 2 A the output transistor is switched on (LOW), below app. 1.5 A it is off (HIGH). The conductor is simply pushed through the transformer.Multiple loops reduce the switching point correspondingly, for instance to 0.5 A with four loops. A supply voltage is not required.ApplicationThe STWA1S is used where current flow is to be detected, with the exact value of the current either known from the power consumption of the connected consumer or does not matter for the evaluation.For simultaneous evaluation of the current flow in several conductors the STWA1S device can be connected in series (AND circuit, pay attention to the voltage drop) or in parallel (OR circuit, pay attention to the leak current).isolated transistor-output max. DC 40 V/40 mAoutput can be directly connected to the digital input of a PLCintegrated diode for reverse voltage protection2-wire-connection, 1 mno supply voltage requiredtransformer and electronic unit enapsulated in a climate-proof housingplug-in current transformer (Ø 11 mm)max. overload 100 A continously, 300 A / 10 s

The STWA1SH is used where current flow has to be detected, with the exact value of the current either known from the power consumption of the connected consumer or does not matter for the evaluation.The STWA1SH has an integrated electronics with transistor-output. isolated transistor-output max. DC 40 V / 40 mAoutput van be directly connected to a digital input of a PLCintegrated diode for reverse voltage protectionelectrical connection via screwless pluggable terminals2- wire, no supply voltage requiredDIN-rail-mount or with screwsplug-in current transformer (Ø 11 mm)max. overload 100 A continuously, 300 A max. 10 s

The STWA1SEH is used where current flow has to be detected, e.g. to report exceeding of a limit, to switch off a machine or just report the current flow. The STWA1SEH has an integrated electronics with transistor-output. The limit is adjustable 2 - 10 A with a potentiometer. A LED displays the state.adjustable switching point 2-10 Abuilt-in LED displays state of the outputisolated transistor-output max. DC 40 V / 40 mAoutput van be directly connected to a digital input of a PLCintegrated diode for reverse voltage protectionelectrival connection via screwless pluggable terminals2-wire, no supply voltage requiredDIN-rail-mount or with screwsplug-in current transformer (Ø 11 mm)max. overload 100 A continuously, 300 A max. 10 s.

The STWA2 AH is a current-transducer for AC currents 0...20/100 A. With the STWA 2 AH the value of a current can be evaluated very economically and space-saving. The output-signal 4...20 mA can be evaluated or displayed with components with analog inputs, e.g. PLCs or ZIEHL digital displays type MINIPAN ®.Overview of Functionscurrent-proportional analog output DC 4...20 mA according to AC-measuring rangemeasuring range (20/100 A) can be changed with bridgeinsulated analog outputsupply DC 9-30 V (via 4-20 mA-loop)electrical connection via screwless pluggable terminalsDIN-rail-mount or with screwsplug-in current transformer (Ø 11 mm)

STWA4MH is a measuring transducer. It measures AC up to 60A and has an RS485 interface (Modbus RTU). The measured analog current value is made available as a digital signal and can be read by a PLC, an IPC or a master computer.The conductor to be measured is passed through an opening (Ø 11 mm). In case of small currents, the sensitivity of the current transducer can be increased by looping through the current-carrying conductor several times, e.g. double looping doubles the sensitivity. The measuring range of the STWA4MH is reduced by multiple looping. To measure currents of any size, the STWA4MH is simply looped into the secondary circuit of a large current transformer with a secondary output of 5A (lead the cable through STWA4MH several times).Application:The STWA4MH enables the space-saving an cost-effective measurement of the actual value of an alternating current. Compared to transducers with analog output, the bus technology significantly  reduces the effort for the hardware (inputs) and the wiring. Applications are e.g. the recording of the current consumption of electrical motors in processing machines. Here the feed can be regulated depending on the load on the motor. Another example is the monitoring of consumers, e.g. heating elements, for failure.