PR200 programmable relay

Programmable relays are also known in the market as:

Compact PLC, Small PLC, mini-PLC, micro PLC, Compact-PLC, industrial controller, Ethernet or RS-485 controller, automation controller.

Programmable relays are programmable logic controllers designed for small industrial automation applications with limited I/O needs. Their small size and simple design make them ideal for space-constrained applications.

You need our programming software ‘akYtec ALP’. It is free of charge. You can find it either on our website or on the USB stick, which is included in the delivery.

Yes, you need a cable (USB A-plug to micro B-plug), which is also included in the package.

There are two ways to connect a Pt100 sensor to the PR200 Programmable Relay:

1. Use the Pt100 macro (see the attachment to this post)
2. Use an analog input of the PRM-X.3 extension module.

Although the first method is completely free to implement, it does not provide enough accuracy. The accuracy of ±5% (52,5 °C) may be too poor for some applications.

If the accuracy is of the utmost importance to your project, the second method is the best solution for you. Having purchased a PRM-X.3, or if you already have one, you can configure any of its inputs for Pt100. In this case, accuracy is ±0.25% (2.6 °C). Since the extension modules of the PRM series are connected to the PR200 over an internal bus, the PR200 treats them as its own, meaning the I/Os of a PRM module are of the same performance as the I/Os of the base unit (PR200).

Since the ‘CLOCK WEEK’ does not have any inputs you cannot change the parameters of this functional block both from the front panel and through variables.

If you need a modifiable ‘CLOCK WEEK’ in your project, two macros are available in the online macro database as well as a sample program that shows how these macros should be programmed.

To download the sample program, please use this link, open and look for the sample project 'Modifiable Week Clock'.

You may refer to the following video to see the instructions on how to download the macros:

This happens because you are trying to import a macro with an already existing ID, though its name and content are different. Most likely, you created one macro, used the command ‘Export macro’, modified this very same macro, and then exported it with a different name. In this case, akYtec ALP assigned an inner ID for the first macro and never changed it even after you had used the Export macro command once again. To overcome this collision, you should have used the command ‘Save macro as…’ before exporting the second macro based on the first one.

The program execution time (cycle time) is automatically adjusted based on the program complexity (Auto-Tuning). The automatic adjustment affects the data exchange via Modbus since program execution takes higher priority over processing requests. If the program is very extensive, it can consume the entire CPU time, and the Modbus data exchange will not be carried out correctly.

To avoid this issue, a lower limit is reserved for the volume of Modbus data exchange: 50 requests per second. This means that at least 50 requests per second can be executed, even if the user program is large, and even more if the program is small and the processor performance is sufficient. If there is not enough time to query all devices, the number of queries in the user program should be optimized.

The setting of the polling cycle depends on the number of variables queried and the polling frequency in the program. It is recommended to set the polling cycle to 1 second. In this case, the device can query up to 50 variables.

The minimum processing time of the program cycle is 1ms, and the signal conversion time for analog outputs is 100ms.

The PR’s has relais outputs, Relay outputs use an electromagnetic coil to actuate a switching contact. When the control voltage is applied to the relay coil, it either closes or opens the switching contacts to control the load.

Whereas PNP transistor outputs are commonly used in control circuits to switch electrical loads, such as relays, LEDs, or motors.

They are e used to provide a positive voltage signal to turn on or control a connected load. When a positive voltage is applied to the base, the transistor becomes conductive, and the collector is connected to the emitter, allowing current to flow to the load.

The main difference is that PNP transistor outputs represent an electronic method for controlling loads, while relay outputs are electromechanical devices. The choice between them depends on the specific requirements of the application and design preferences.

To write to or read from a functional block, it is necessary to use the blocks 'WriteToFB' or 'ReadFromFB', respectively. You can find these blocks on the toolbar ‘Insert’.

You may refer to the following video to see instructions on how to use these tools:

Digital Input: 264 V AC (for 230.x.x Version) 30VDC (for 24.x.x version)

Digital Output: AC 5A, 250 V DC: 3A, 30V

To configure the input hardware: – remove the front cover – set the jumpers on the respective jumper block XP in accordance to the expected input signal using a thin tool (e.g. tweezers) – close the front cover.

The main and the simplest way to do it is to use the PRM Extension Modules from akYtec. With these modules, you can extend the PR200 by up to 16 additional digital inputs and up to 16 digital outputs. Alternatively, if your system requires more I/O-points, you can use Modbus RTU/ASCII and connect up to 32 expansion modules over the RS485 interface. We recommend using our I/O-Modules of the Mx110 series for this purpose.

In general it is possible to use the PR200 in the slave mode but note:

when a device is configured as a Modbus RTU Slave, it generally cannot accept unsolicited messages or write commands directly from the Master. The Slave can only respond to read requests (queries) from the Master. This means the Master can request data from the registers of the Slave (e.g., Holding Registers, Input Registers, Discrete Inputs), but the Slave will not actively send data or accept write commands from the Master.

 

In the Slave mode, the following network functions are possible:

 

• Read digital I/O status
• Read analog I/O value
• Read / write network variables
• Read / write Real-Time Clock data

 

To configure the PR200, you will need the akYtec ALP. ALP stands for the programming software for the PR200 and many other devices from akYtec. However, please note that the write function is limited to specific resources. Therefore, you should consider whether the PR200 is suitable as a Slave to meet your requirements. Also, it is advisable to ensure that the used Master device is compatible with the akYtec ALP to facilitate a smooth setup.

A module of Mx110 series can be connected to the PR200 via the RS485 interface and Modbus protocol.

Yes, the PR-devices series can be used to monitor and control the consumption of a PV system. The PR series supports the Modbus RTU protocol, making it compatible with any energy meter that supports this protocol. The digital outputs of the series are suitable for control purposes and can, for example, redirect the current to a battery, the general power grid, or heating elements

This frequency depends on the device variant.

PR200-230.X.X:10 Hz

PR200-24.X.X: 250 Hz.

In either case, a square wave pulse signal with 50% duty cycle is assumed.

The user program is written to the retain memory. The battery can be changed without any issues, and the program remains unaffected. It's worth noting that when the battery is replaced, the RTC will be reset. The battery typically lasts for about 8 years.

It depends on the switching current of the power contactor. A relay output of the PR200 has the following switching capacities:

AC: 5 A, 250 V (resistive load)

DC: 3 A, 30 V. 

Any HMI device compatible with the Modbus RTU Protocol is of displaying process values and can be utilized as an HMI with the PR device series.

No, this voltage source cannot be used for feeding an Mx110 module because it doesn’t provide enough current (max. 100 mA). However, this current is enough for both an ITP display or its analog output.

The program is stored in the retain memory, which remains unaffected in the event of a power failure. Therefore, in the event of a power failure, your PR device will retain the program and will not require reprogramming. Variables that must be stored in non-volatile memory must be marked as retain in the ALP project.

It depends on the device variant:

PR200-230.X.X: 159 V and 0.75 mA.

PR200-24.X.X: 15 V and 5 mA.

Yes the PR-devices can function as PID-Controller, our ALP Software utilizes function block language and comes with preinstalled macros like PID Controller and PWM Generator, among others.

It depends on the type of the variables. They can be either INT or REAL. An INT variable stores data in only one register, while a REAL variable requires two registers for this.

Since the PR200 as Modbus Slave have only 64 registers, it means the maximum number of variables is:

64 if you declare only INT variables

32 if you declare only REAL variables.

If there are both INT and REAL variables, you should calculate their maximum permissible number according to their combination. For example, if you declare 10 REAL variables, which is equal to 20 INT variables, you can declare up to 44 INT variables (64 - 20 = 44).

Yes, the PR-Devices can be used to control pumping systems. Therefore, we recommend exploring the sample projects available on our website. We also offer sample projects that showcase the capabilities of PR devices, such as a press machine.

In one of these projects, we demonstrate how the programmable relay PR200 can be utilized to enhance operator safety when operating a press machine. Additionally, a counting function has been implemented, and its results are displayed.

Another example project involves a modifiable week clock. Some automation tasks require toggling secondary devices based on specific schedules, which can change over time. With this sample project you can learn how to set more importantly, modify the schedule of output activities using the PR’s function keys and screen.

The PR200 as Modbus Master can control up to 16 Slave Devices over each RS485 interface. Each Slave Device can process up to 256 variables.

If the accuracy of the input or output of the module is no longer in accordance with the specification, it can be calibrated.

Each analog input and output has its own calibration coefficients for each sensor type.

– The calibration is performed using a reference signal source connected to the device input or output.

– The calibration coefficients are calculated based of the ratio between the current input signal and the reference signal and stored in the non-volatile device memory.

– If the calculated coefficients go beyond the permissible limits, a message about the error cause will be displayed.

For further concrete instructions on page 36 in the manual shows step by step instructions on how to calibrate input/ or output

Yes, this application is possible.

You need two network variables, one per interface. Then you just link them by means of the tools ‘Network variable input block’  and ‘Network variable output block’ . For step-by-step instructions, please watch this video:

Only positive INT values can be stored in the Modbus registers. Positive values in the range of 0 to 32767 are stored as usual. To write a negative number in Modbus registers, you need to add 65536 to that number. For example, the number – 1 corresponds to 65535 in Modbus registers and -100 corresponds to 65436. In Akytec ALP you can find the INT16 macro in the component manager, which performs this conversion and outputs either an INT or a REAL value.

First of all, this problem can be caused by a wrong position of jumpers. There are two jumpers, XP4 and XP5, on the RS485 interface card of the PR200. They can be set either to Master or to Slave:

By default upon delivery, they are set to Slave. To use the interface as Master, the jumpers must be set to the M position:

If the jumpers are set to Master and the communication problems still occur, you should check if:

- all the devices on the network have the same network parameters (protocol, baud rate, parity, stop bits and data bits)

- there is only one Master (in this case the PR200) on the network

- all wires are connected properly and there are no loose wires

- signal cables are screened or routed separately from power cables

- the secondary devices on the network are connected to the PR200 in a linear (bus) topology, meaning each device is directly connected to a common line (the bus), and all signals are transmitted from one end to the other

- there are terminating resistors at both ends of the communication bus. Experience shows that the most efficient practice is to use terminating resistors of 150 ohm.

Modbus registers work as a way to store and exchange data in Modbus communication, which is a popular protocol used in industrial automation and control systems. Modbus registers are typically 16-bit values, and they are indeed represented in hexadecimal format. Here's an explanation of how Modbus registers work and why hexadecimal is used:

The register address has to be written in decimal.

To read and show REAL variables, it is important to know the endianness of the registers and bytes, i.e. register and byte ordering. It can be either big-endian or little-endian format.

If you use the big-endian format, the register or the byte that contains the most significant bit is sent first, followed in a decreasing significance order. The little-endian format has a reversed order.

You can determine the register and byte order using respective checkboxes on the Device Configuration dialog box (Device > Device settings):

First, you should choose the required jumper position according to the figure below:

You can find the jumpers under the front housing:

All analog inputs are set to 4-20 mA in the delivery state.

Second, you have to set the required input type in akYtec ALP:

- From the Menu bar, select Device > Device settings or click the Device settings button 

- In the tree view on the left, find the node Inputs, click Analog and select an analog input

- On the right, select the required input type on the Input Signal drop-down list and set the required lower and upper limits

- Click Close to save and exit.

You need to update the firmware in the ‘Down.Mode’ mode.

First, remove the front housing of the PR200 and set a jumper on the XP3 connector:

The ‘Down.Mode’ mode has been activated. Open akYtec ALP and select Device > Firmaware update from the Menu bar:

Select your device from the list and press the Select button.

Maximum two modules can be connected in series to PR200.

With these modules, you can extend the PR200 by up to 16 additional digital inputs and up to 16 digital outputs. Alternatively, if your system requires more I/O-points, you can use Modbus RTU/ASCII and connect up to 32 expansion modules over the RS485 interface. We recommend using our I/O-Modules of the Mx110 series for this purpose.