RAZORBILL MP240 User Manual

High isolation multiplexer

Hide thumbs

Table Of Contents

Table of Contents

Quick Links

Download this manual

USER MANUAL

MP240: HIGH ISOLATION

MULTIPLEXER

The MP240 is a Double pole, quad throw fully shielded coaxial

multiplexer designed for use in high impedance measurement

systems.

This multiplexer can be used in conjunction with other Razorbill

Instruments products, it is ideal for use with devices such as the

UC200 that contain more than one capacitive sensor, or in cases

where more than one stress or strain cell is used simultaneously.

The MP240 may be controlled by USB or by a digital input. The

digital input is compatible with Andeen-Hagerling capacitance

bridges.

Version 1.1 (released 14 April 2021)

http://razorbillinstruments.com

Page 1 of 40

Table of Contents

Need help?

Do you have a question about the MP240 and is the answer not in the manual?

Questions and answers

Summary of Contents for RAZORBILL MP240

Page 1 UC200 that contain more than one capacitive sensor, or in cases where more than one stress or strain cell is used simultaneously. The MP240 may be controlled by USB or by a digital input. The digital input is compatible with Andeen-Hagerling capacitance bridges.
Page 2: Scope Of Use
This document is designed to allow the end-users to safely and efficiently set-up and operate the MP240 High Isolation Multiplexer and use it in conjunction with other Razorbill Instruments products. The document is also designed to draw attention to any risks and hazards involved in operating the MP240 and the steps necessary to minimise them.
Page 3: Table Of Contents
Table of Contents ..............3 CE Declaration of Conformity..........6 UK Declaration of Conformity ..........7 Supplier’s Declaration of Conformity (USA) ......8 Disposing of your MP240 ............9 Suitable Operating Environments .......... 10 Operating Modes ..............10 Getting Started ............... 11 Reading the Front Panel ............
Page 4 SYSTem commands ............31 ROUTe commands ............. 32 MODE commands ............. 35 Example Code Snippet ............37 Caring for your MP240 Multiplexer ........38 Installing a Firmware Upgrade .......... 38 Cleaning ................38 Firmware licencing information..........38 SCPI-PARSER ............... 39 LUFA ................
Page 5 Length 180 mm Width 185 mm Size Height 65 mm Weight approx. 1.2kg USB operation 5 V, 200 mA Power supply Digital Input Port 5V, 100 mA Max voltage 30 V Recommended current < 10 mA Switched Signal Max switching current 400 mA Max carrying current 1000 mA...
Page 6: Ce Declaration Of Conformity
CE DECLARATION OF CONFORMITY Manufacturer Razorbill Instruments Ltd Manufacturer’s Unit 8 Address Castlebrae Business centre 40 Peffer Place Edinburgh EH16 4BB CE Mark The manufacturer hereby declares that the product Product Name High Isolation Multiplexer Model Number MP240 has been tested to the following standards...
Page 7: Uk Declaration Of Conformity
UK DECLARATION OF CONFORMITY Manufacturer Razorbill Instruments Ltd Manufacturer’s Unit 8 Address Castlebrae Business centre 40 Peffer Place Edinburgh EH16 4BB UKCA Mark The manufacturer hereby declares that the product Product Name High Isolation Multiplexer Model Number MP240 has been tested to the following standards...
Page 8: Supplier's Declaration Of Conformity (Usa)
Razorbill Instruments Ltd Unit 8, Castlebrae Business centre 40 Peffer Place, Edinburgh EH16 4BB MP240 High Isolation Multiplexer complies with the applicable requirements of FCC Rule Part 18 RESPONSIBLE PARTY located in the United States: Testing Partners LLC 18200 SR 306 Chagrin Falls, OH 44023 info@testingpartners.com...
Page 9: Disposing Of Your Mp240
DISPOSING OF YOUR MP240 As an electrical good, the MP240 must not be thrown away in normal waste disposal for environmental and ecological reasons. For products sold to and owned by institutions based within the EU or UK, Razorbill Instruments will be happy to arrange for this product to be picked up and disposed of properly at the end of this products life.
Page 10: Suitable Operating Environments
SUITABLE OPERATING ENVIRONMENTS The MP240 multiplexer must only be used under the following operating conditions • Indoor use only • Ambient temperature 5°C - 40°C • Humidity < 80 % (non-condensing) OPERATING MODES The MP240 has three operating modes, which are determined by which cables are connected to the rear panel: USB Only.
Page 11: Getting Started
Low relay bank, common terminal switched terminals Figure 1. The front panel of the MP240 As the primary mode of control of the multiplexer is using serial commands over a USB connection, the front panel does not feature any input controls and provides only limited information via 6 LED indicators.
Page 12 H . These would typically be connected to the yellow- marked coax cable on a Razorbill instruments strain cell, or to any other device you with to measure Version 1.1 (released 14 April 2021) http://razorbillinstruments.com...
Page 13: Back Panel Layout
L . These would typically be connected to the black-marked coax cable on a Razorbill instruments strain cell, or to any other device you wish to measure Back Panel Layout...
Page 14: Typical First Time Set-Up
SCPI commands defined in this document. The supplied cable is good quality and includes EMI suppression ferrites. The MP240 was tested for EMC compliance with this cable and is not guaranteed compliant with other cables. Version 1.1 (released 14 April 2021) http://razorbillinstruments.com...
Page 15: Technical Discription
Use with Andeen-Hagerling Bridges When used with a capacitance bridge from Andeen-Hagerling, the USB connection is not required, and noise will be lower if it is not connected. If it is not connected, the front panel LEDs will not illuminate. The bridge should be configured with an average time of 7 or higher.
Page 16 jumper wires from the relay boards to the case . When the jumpers are removed, analogue ground is derived from the shield of the connected cables in each bank. Figure 3 - block diagram The case ground is connected to the USB ground and digital input port ground.
Page 17: Usb Serial Communication
USB cable. USB Serial communication The MP240 multiplexer uses a USB virtual serial port to communicate with a computer. The multiplexer acts as a bus- powered USB2.0 full speed device, and requires up to 200 mA from the computer or USB hub to which it is connected.
Page 18: Linux, Mac Os And Other Systems
Linux, Mac OS and other systems The MP240 implements USB CDC and is likely to work on most modern platforms. We are not able to offer assistance with communications issues on operating systems other than Microsoft Windows.
Page 19: Pin Allocations
Pin allocations The pins are numbered according to Figure 4 and the pin numbers are also moulded into the connector. The pin allocations are shown below: Function Channel 1 Enable Channel 3 Enable Ground Power (+5 V) Channel 2 Enable Channel 4 Enable Shell Ground...
Page 20: Electrical Ratings
operates, disconnect the power supply or capacitance bridge. The fuse will automatically reset within a few minutes. Power supplied to pin 6 from a source other than an Andeen Hagerling capacitance bridge must be well-regulated and should have the minimum practicable noise or ripple. Power supplied in this way will be used to operate the relays.
Page 21: Scpi Command Reference
SCPI COMMAND REFERENCE The multiplexer accepts a variety of simple commands, and is designed to comply with the Standard Commands for Programmable Instruments (SCPI) standard. The commands will be described using the following notation: A keyword, which may be written in full or abbreviated to only the letters in capitals.
Page 22: Command List
The commands listed here are supported by the 1.0.0 version. Future firmware versions may add more commands and functionality. An up-to-date manual will be made available on the Razorbill Instruments website with each firmware update. Version 1.1 (released 14 April 2021) http://razorbillinstruments.com...
Page 23: Scpi Core Commands
COMMAND DESCRIPTION PAGE *CLS System clear *ESE[?] Error status exe *ESR? Error status *IDN? Identification request *OPC[?] Operation complete? *RST Reset device *SRE[?] Service request enable *STB? Get status byte *TST? Self test *WAI Wait for operation SYSTem:ERRor[:NEXT]? Get last error SYSTem:ERRor:COUNt? Get number of errors [ROUTe]:SELEct #...
Page 24 *CLS No response Description Clears status data structures device, including all status registers and the error queue. *CLS Example *ESE No response *ESE? <int> Description Set or query the Standard Event Status Enable register. This command is required for SCPI compatibility, and is only minimally supported.
Page 25 *ESR? <int> Description Query the Standard Event Status Register. This command is required for SCPI compatibility, and is only minimally supported. Refer to the SCPI standard for more information. *ESR? Example Version 1.1 (released 14 April 2021) http://razorbillinstruments.com Page 25 of 40...
Page 26 *IDN? <str1>,<str2>,<str3>,<str4> parameter <str1> The device manufacturer. Always Razorbill parameter <str2> The device model. Always MP240 parameter <str3> The six-digit serial number, as a string, e.g. 000001 The firmware version number, e.g. parameter <str4> 1.0.0 Description Query the device identity information.
Page 27 *OPC No response *OPC? Description The command form sets the operation complete flag. This command is required by the SCPI standard, but has no effect as the flag is always set. The query form queries the operation complete flag, and will always return 1.
Page 28 *SRE No Response *SRE? <bool> Set or query the service Description request enable flag. This command is required for SCPI compliance, but even with service requests enabled, the multiplexer will never raise them. So this command has no effect. *SRE? Example Version 1.1 (released 14 April 2021) http://razorbillinstruments.com...
Page 29 *STB? <int> Parameter <int> The status byte expressed as an integer between 0 and 255. Description Read the Status Byte from the instrument. Although response is an integer, it represents individual bits/flags. Only bit 2 is used multiplexer, indicates an error is in the error queue.
Page 30 *WAI No Response Wait for the current operation Description to complete. This command is required for SCPI compliance, but all there are no commands which take time to execute, so the instrument will never wait. *WAI Example Version 1.1 (released 14 April 2021) http://razorbillinstruments.com Page 30 of 40...
Page 31: System Commands
SYSTem commands These commands are used to obtain information about the error queue. If the multiplexer detects an internal error, or it cannot parse a command from the PC, it will generate an error. Errors are stored in a queue, first in, first out, and as long as there is something in the queue the error LED on the front panel will be lit.
Page 32: Route Commands
SYSTem:ERRor:COUNt? <int> The number of errors in the Parameter <int> queue. Retrieves the number of errors in Description the error queue. The queue can store at most 16 errors, if that number is exceeded, the last error in the queue becomes a queue overflow error, and the other errors are discarded.
Page 33 [ROUTe]:SELEct <int> No response [ROUTe]:SELEct? <int> Parameter <int> The channel to operate on, 0 to 4 Description The command exclusively sets a route in both high and low relay banks. Any other relays that were previously enabled are disabled. If called on channel 0, all relays are disabled The query form returns 0 if no relays are enabled, 1 to 4 if a route is...
Page 34 [ROUTe]:<bank># <bool> No response [ROUTe]:<bank>#? <bool> Parameter 1 means the specified front panel BNC <bool> connector will be internally connected to the corresponding BNC connector marked COM. 0 means the specified front panel BNC connector will be grounded. Parameter H or L, corresponding the high and low relay <bank>...
Page 35: Mode Commands
MODE commands The MODE command is used to put the device in and out of serial monitoring mode. If the USB is connected, the device will always start in USB control mode and MODE:EXT can be used to hand over control to the digital input port. MODE:EXT <bool>...
Page 36 MODE:PWRSource? <bool> Parameter 1 means the device is using power from the <bool> digital input port to control the relays. 0 means power is being derived from USB This query allows the user to check which Description power source is being used to operate the relays.
Page 37: Example Code Snippet
SELECT 2 SELECT 0 And here is an example of how you might achieve that in Python (requires PySerial to be installed): import serial import time with serial.Serial('COM1') as mp240: mp240.write(b'SELECT 1\n') time.sleep(1) # take a measurement here mp240.write(b'SELECT 2\n') time.sleep(1) # take a measurement here mp240.write(b'SELECT 0\n')
Page 38: Caring For Your Mp240 Multiplexer
Note that the authors of the open- source projects do not give any warranty on the code, but this does not impact the warranty provided by Razorbill Instruments, which covers the complete multiplexer, including firmware. Firmware components which are not part of the open source components are copyright 2020 Razorbill Instruments Ltd and are not to be reproduced without permission.
Page 39: Scpi-Parser
SCPI-PARSER Copyright (c) 2012-2013 Jan Breuer, All Rights Reserved Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
Page 40: Lufa
LUFA LUFA Library Copyright (C) Dean Camera, 2012. dean [at] fourwalledcubicle [dot] com www.lufa-lib.org Permission to use, copy, modify, and distribute this software and its documentation for any purpose is hereby granted without fee, provided that the above copyright notice appear in all copies and that both that the copyright notice and this permission notice and warranty disclaimer appear in supporting documentation, and that the name of the author not be used in advertising or publicity...