Question 1

What is the meaning of the utilisation categories AC1 and AC3  for the Tesys contactors?

Accepted Answer

The standard utilisation categories defines the current making and breaking values for contactors.They depend on the following: The type of load to be controlled (squirrel cage or slip ring motor, resistors etc.)The operating cycle conditions (motor running, stalled or starting, reverse operation, counter-current braking etc.) AC-1 category This applies to all AC devices (loads) with a power factor of at least 0.95 (cos phi greater than or equal to 0.95).Examples of use: resistive load, heating, distribution AC-3 category This applies to squirrel cage motors where breaking occurs while the motor is running.Examples of use: all squirrel cage motors, lifts, escalators, conveyors, bucket elevators, compressors, pumps, mixers, air conditioning units Note concerning contactor part numbers The most common application of contactors is controlling squirrel cage asynchronous motors.Hence, Schneider Electric contactor part numbers are based on the AC-3 rating. For example, the LC1D18xx contactor is designed to control motors with a nominal current rating of 18 A (AC-3).This contactor is capable of withstanding current peaks (~ 100 A) on starting, such as are typical on inductive machines like motors, without sustaining any damage.It can also control resistance heaters for current ratings up to 32 A (AC-1). This load is resistive, hence there are no current peaks.Utilization categories are defined in full in regulation IEC 60947-1

Question 2

Can 80A or 100A miniature circuit breakers be fitted onto the outgoing ways of the Acti9 Isobar Distribution Boards?

Accepted Answer

The Acti9 Isobar Distribution Boards outgoing ways are designed to be fitted with iC60H MCB's up to and including 63A.MCB's rated at 80A and above are physically larger and do not fit the isobar busbar system.However , there is a way around this:By installing a SEA9BNEX034N below the board and fitting an 80A iC120H MCB in this enclosure you can then feed from the board (via an SEA9TB1001) terminal block in to the iC120HFor single pole MCB's use 1 x SEA9TB1001 for 3 pole MCB's use 3 x SEA9TB1001.

Question 3

What is a Shunt Trip MX used for?

Accepted Answer

A Shunt Trip coil is used to remotely trip a circuit breaker and some switch disconnectors.Schneider Electric uses the abbreviation MX or iMX for Shunt Trip coils.A Shunt Trip coil has to have a voltage applied to it to trip the device.An example of an application for a Shunt Trip would be for load shedding.A second example would be for an EPO circuit with N/O EPO contacts wired in parallel.

Question 4

Can the new Easy9 and Easy9+ MCB's and RCBO's fit the older Domae consumer unit?

Accepted Answer

Yes, both the Easy9 and Easy9+ MCB's and RCBO's will fit the older Domae consumer unit and any of the older Domae range of consumer units.Examples of Domea consumer units below; DOM2CUDOM4CUDOM6CUDOM8CUDOM12CUDOM16CUDOM20CU

Question 5

What is the pin-out of the cable XBTZ915?

Accepted Answer

Below is the pin-out of cable XBTZ915

Question 6

What is the cabling diagram for the SR1CBL01 cable?

Accepted Answer

NOTE that SR1 relays are obsolete, replaced by SR2 and SR3. Click on the product link on the right for more information. The SR1CBL01 is the programming cable to be used with the Zelio Relay SR1.To be able to connect first generation Zelio programmable relays (part number SR 1xx) to a PC supporting the ZelioSoft programming software (part number SR1SFT01) you must have the SR1CBL01 programming cable.The wiring diagram is as follows: Zelio connector end: brown: 2, yellow: 7, red: 3, orange: 5. PC SubD9 end: brown: 7, yellow: 2, red: 3, orange: 5.Please Note: This cable and configuration is for the Zelio Logic First Generation - These items will not work with SR2 devices, Zelio Logic 2, or Zeliosoft2 Programing Software.*********************************************************NOTE*******************************************************************The Zelio SR1 software , devices and modules are discontinued. Please check the Zelio Smart Relay SR2 or SR3.***********************************************************************************************************************************

Question 7

In a star-delta starter, how can I incorporate a thermal overload relay as per Type 1 or Type 2 coordination?

Accepted Answer

Only tests carried out by accredited laboratories allow the announcement that a combination of equipment can protect the installation according to type 1, type 2 or total coordination.These combinations are very clearly specified in tables by the manufacturer (Schneider Electric) and do not allow any exceptions. See the link to these tables at the end of the folder.When using a star/delta starter, the required level of coordination for the installation determines:The ratings and part numbers of the 3 contactorsThe ratings and part numbers of the circuit-breakers or isolatorsThe rating, part number and position of the thermal overload relay in the sequenceType 1 coordinationThe thermal overload relay is placed in the delta circuit and must be set to 0.58 x motor In.The relay is less expensive as it has a low rating.Type 2 coordinationThe thermal overload relay is placed under the line contactor and must be set to motor In. It is not possible to obtain type 2 coordination by placing the thermal relay in the delta circuit.The product is protected irrespective of the operating phase.Information on coordination: Coordination 1 and 2For extra info see attached selection guide taken from section A6 of our Motor Control and Protection catalogue

Question 8

What size fuses can be fitted into YW6 fuse handles?

Accepted Answer

YW6 Fuse handles accept 92mm centres 'J' type fuses to BS88 part 5 rating up to 630A.

Question 9

What does light or dark switching mean when referring to photo electric sensors?

Accepted Answer

Please note - As of 01/09/23 the Telemecanique Sensors range is no longer part of Schneider Electric. This FAQ is now for reference only. For further information and contact details for Telemecanique Sensors, please visit their website; https://www.telemecaniquesensors.com/uk/en There are 3 main types of photo electric sensor used for detecting an object; Diffuse (sometimes also called proximity mode or direct detection). There is also a variation of diffuse called diffuse with background suppression (diffuse with BGS).Retro reflective (sometimes also called reflex). There is also a variation of reflex called polarised reflex (or polarised retro reflective). Through beam (sometimes also called thru' beam). Determining normally open (N/O) or normally closed (N/C) operation? Both the retro reflective and through beam sensors rely on the object 'breaking' the beam in order for it to be detected. Whereas the diffuse system requires the object itself to reflect the light beam.Because of this fundamental difference in the way the sensors detect an object, retro reflective and through beam sensor outputs are the inverse of diffuse sensors. This leads to a lot of confusion. Historically Within the photo electric industry, to overcome the confusion of referring to N/O or N/C outputs, the term 'light switching' and 'dark switching' was introduced; Light switching; A sensor that is light switching switches it's output 'on' when the light beam is returned to the receiver. i.e. If N/O operation is required, a light switching diffuse sensor could be used. Dark switching; A sensor that is dark switching switches it's output 'on' when the light beam blocked from returning the beam to the receiver. i.e. If N/O operation is required, a dark switching retro reflective or through beam sensor could be used. Recent developments To simplify product selection, Schneider Electric (under the Telemecanique brand) pioneered the concept (launched as Osiconcept) of 'object detection' with it's Osiris multimode range of sensors. With these products, irrespective of whether the sensor is configured for retro reflective, through beam or diffuse the output will default to N/O. Another feature of these multimode sensors is the ability to invert the output to achieve a N/C mode of operation.

Question 10

How can I cable to the PNP and NPN type outputs for sensors / detectors, using the wiring diagram?

Accepted Answer

PNP and NPN type outputs are available as 3-wire sensors with a DC voltage power supply (the voltage limits are dependent on the specific sensor): PNP type: switching on the positive voltage load NPN type: switching on the negative voltage load These outputs are typical of photoelectric detectors, inductive proximity and other types of sensors.For a detailed explanation of PNP vs NPN, see the following FAQ: FA142566 PNP output The load (relay coil, contactor relay input, PLC input) must be connected between the "-" negative terminal and the midpoint. The corresponding PLC input is Sink. NPN output The load must be connected between the "+" positive terminal and the midpoint. The corresponding PLC input is Source. Some sensors have two PNP and NPN outputs (4-wire sensors) which are wired according to the diagram below.Note that we no longer sell sensors. Telemecanique Sensors, who were previously part of the Schneider Electric brand, were sold in 2023. You can go to their website - www.telemecaniquesensors.com - for more information, including contact details.

Question 11

Why is Neutral and Earth (Ground) Connection forbidden Downstream from Main Panel?

Accepted Answer

The question is often asked what is the maximum voltage permitted between the Neutral and Earth (Ground) conductor and if the Neutral and Earth can be bridged to achieve a zero value.This can be a difficult topic, in fact in many cases it can be dangerous. As you will see from the attached document, there are many reasons why it is not allowed.

Question 12

What are the differences between snap-action and slow-break contacts in limit switches?

Accepted Answer

Note we no longer sell limit switches so the information given below is for information purposes only. You may still be able to buy Telemecanique limit switches (and some 9007 etc. ex-Schneider Electric ranges) but you'd need to go to them directly. This is their website for contact details and product information: www.telemecaniquesensors.com Snap actionThe speed of travel of snap-action contacts is not related to the speed of operation of the actuator. The actuator pretensions an "overcentre spring" mechanism and it is the spring tension which operates the contact once a certain tension has been achieved. This results in a very fast and assured operation of the contacts as the spring mechanisms "flicks" (or "snaps") over the trigger point and latches the contacts on. A similar action takes place on the release, i.e. as the actuator is released the spring tension reduces but the contacts do not move until the tension has dropped below a certain level, when the spring mechanism will snap the contacts open again.Slow BreakA "slow break contact" is one where the physical movement of the actuator is directly linked to the physical movement of the contact. This can give very precise positioning and synchronization of both make and break points but is susceptible to arcing and intermittent signalling at the crucial make/break position, where actuator movement is slow and/or erratic.Main differences between Snap Action and Slow BreakThe snap action contact mechanism inevitably creates a hysteresis effect, where the closing and opening of the switch have considerable overlap. Please see attached timing diagram example. This does not occur with slow break, as the movement of the contacts is directly linked to the movement of the switch / object.Slow break have a higher minimum actuation speed, to overcome the effect of sustain arcing on the contacts. Note that for applications that cause the switch to open a little and then re-close repeatedly / rapidly, this can reduce electrical durability over time.Both types commonly have positive opening N/C contacts (always check your switch to confirm), but snap action provide an assured signal at slower speeds, whereas slow break rely on the minimum actuation speed. This is why there is potential for intermittent signalling on slow break, if that minimum speed is not adhered to.Slow break can often switch bigger loads and offer higher electrical reliability values compared to snap action but please check product tables / data to confirm this on a case-by-case basis.Sequence of moving contactsTiming Sequence for "Snap Action". Note overlap of switching positions for different directions of travel.Timing sequence for "Slow Break". Note same position for make and break.

Question 13

How does the "Dead man's switch" or "Dead man's handle" position work on a controller handle?

Accepted Answer

Please note that we no longer sell joysticks, so this FAQ is for information only. Technological description The handle grip comprises a fixed part (lower section) and a moving part (upper section).Action on the upper part of the handle grip (pressing down) drives a sliding rod inside the control lever.This rod actuates a moving retainer which causes a change in electrical state of the contact element on the lower part of the mechanism, regardless of the position of the control lever. Operation In normal operation, the operator must maintain pressure on the handle grip to operate the machine.If the operator releases pressure (e.g. feels ill and passes out), even if they are still holding on to it, the electrical contact at the base will change state.

Question 14

What is the difference between the REFLEX mode and the POLARISED REFLEX mode on photo-electric sensors?

Accepted Answer

Note that we no longer sell these devices, this FAQ is for information only. Both systems comprise a transmitter and receiver (usually within a single-body sensor), and a reflector. The transmitter sends a beam which is bounced back by the reflector and detected by the receiver. An object passing through the beam blocks the reflection and triggers the sensing signal.REFLEX mode sensors may not be suitable for detecting reflective objects, as a shiny target may bounce the beam back to the sensor in the same way as the reflector. The sensor may not be able to tell the difference between the target and reflector and will therefore fail to detect the object. For maximum effectiveness the targets should be opaque or near opaque and should not be highly reflective in nature. However, the advantage of reflex mode sensors is that they give relatively long sensing distances.POLARISED REFLEX mode sensors have polarising filters over both the transmitter and receiving sensor. The filters are at 90 deg to each other which means that the receiver cannot see the transmitted beam as it will be blocked by the receiver filter. The reflector turns the polarised light waves through 90 deg so that the receiver can see them. Light bouncing off other objects is not rotated so it will not trigger the sensor. This means that the polarised reflex can be used to detect very reflective surfaces, even mirrors, polished metal and semi transparent materials. However, the sensing distance is shorter than REFLEX.

Question 15

How do I operate a star delta starter with 2 wire control?

Accepted Answer

First it is necessary to understand the difference between 2 and 3 wire control. Most motor systems that require operator action to start a motor use 3 wire control. This is a method by which a pulse of control voltage is applied, usually through a momentary pushbutton or spring return selector etc, to the control circuit. The pulse will bring in a contactor or relay which will electrically latch through one of it's own normally open contacts to hold itself in once the start button is released and the pulse removed. The stop button is usually a normally closed contact in series with the supply to the start button and coil of the latching relay, so that when pressed the contact will open, break the supply to the coil and the relay/contactor will drop out, and remain out, until the start device is again operated. Below is a simple diagram illustrating the principle of three wire control. Two wire control is much simpler, a straightforward on/off switch will do the job. Applying power to the control circuit starts the motor, removing the control voltage stops it. Below is a schematic of how a star delta starter can be operated in two wire control. 96 is the terminal for the NC contact on the overload relay, the run signal will be applied to terminal 95 to enable the overload to switch off the motor in the event of a motor fault. KM1 is the Star contactor, KM2 is the Line contactor and KM3 is the Delta. The timer is most commonly a pneumatic timer fitted to KM2 and will normally operate a few seconds (typically 5-30 seconds) after KM2 has energised. This type of operation will usually be found where a star delta is to be operated by a PLC, a pressure or temperature switch or some other device which is going to provide a simple on/off signal. Although 2 wire operation is theoretically simple, it does introduce some problems. Where the possibility of physical interaction between people and a piece of driven machinery exists it is necessary to prevent unexpected re-starts after an overload reset, power resumption after a power cut, emergency stop reset etc. 3 Wire control achieves this automatically as the latching contactor will drop out after a supply or control interruption and will not restart until another start signal is given. With two wire control the machine will restart immediately when power is restored unless the control signal has first been removed. This may not be an issue on an enclosed system, perhaps a ventilation system with enclosed fans etc but on something like a machine tool, saw, conveyor etc, it is essential that an opportunity is given for an operator to ensure everything is clear before initiating a restart. If control is by PLC or similar it may be possible to build into the software to detect an unintended stop and then require a reset input to the PLC before the PLC can restart the motor. Alternatively, an electromechanical system of de-energise and reset of control voltages could be applied. This may be a suitable solution where motors are controlled by a pressure or temperature switch etc. Attached is an example diagram of how such a circuit might be applied to a pressure switch. In this case, once a start signal has been applied the motor will be under the control of the pressure switch, but after a supply or control circuit interruption it will be necessary to press the start button again to reset the control circuit. Any emergency stop application must be upstream of the overload to ensure that in the event of an emergency stop the control circuit will be de-energised requiring a “Start” signal to reset the control supply.

Question 16

What is the difference between PNP and NPN when describing 3 wire connection of a sensor?

Accepted Answer

Most industrial proximity sensors (inductive, capacitive, ultrasonic and photo electric) are solid state.The term solid state refers to the type of components used within the sensor. Solid state electronic components such as transistors are used to switch the output of the sensor upon detection of an object.Two specific types of 3 wire sensors are available; PNP and NPN. The difference is a result of the internal circuit design and type of transistors used. Refer to attached document for simple explanation of the two.A key point to observe is that PNP and NPN has nothing to do with whether the sensor is normally open (N/O) or normally closed (N/C), i.e. a PNP sensor may be either N/O or N/C as can an NPN be either N/O or N/C.Please note that the subject of this FAQ is specifically related to wiring PNP/NPN outputs for sensors, not to give a detailed understanding of transistor technology. However, for ease of understanding please see attached a page extracted from our Practical Aspects book, showing (in brief) transistor terminology and circuit diagrams. Further learning material regarding PNP and NPN transistors can be found online from several sources. Why two types?The selection of a PNP sensor verses an NPN sensor is determined by the nature of the circuit the device is to be used in. When used in a traditional relay type control circuit, it is normally possible to use either the PNP or the NPN type of sensor as shown below. PNP sensors tend to be more commonly used. WiringTraditional relay type control circuit; Use with a programmable logic controller (PLC).When selecting a sensor to be used with a PLC, it is very important that the sensor matches the type of PLC input card to be used.Two types of input cards exist, those that 'sink' current (also known as positive logic) and those that 'source' current (also known as negative logic). It is worth mentioning, that whilst the terms sinking / sourcing and positive / negative logic are well known in some industries, they are not always commonly used terms. It is therefore important to identify the type of sensor to be used with the PLC card based on the PLC manufacturer's documentation and / or wiring diagrams.Most common in Europe is the 'sinking' type of input, these will be used with the PNP sensor as shown below. Less common nowadays are input cards that 'source', these were popular in Asia and require the NPN type of sensor in order to operate correctly. Many modern PLC input cards can be configured and wired to be either 'sinking' or 'sourcing' although it will usually necessitate all inputs on a particular input card being configured the same. NOTE the dotted line in the following diagram is optional and may or may not be required, depending on your hardware/setup. The key wires to take note of are solid red, black and blue wires.

Support Centre

Download Centre

Support Centre

Download Centre

Support Centre

Download Centre

Products

Support

Company

Quick Links

Partners

Sustainability

Events

Insights
opens new tab