Danfoss PVED-CX User guide
Technical Information
Electrohydraulic Actuators
PVED-CX Series 4
powersolutions.danfoss.com
Technical Information
PVED-CX, Series 4 Electrohydraulic Actuator
Revision history Table of revisions
Date Changed Rev
Jun 2017 Spool positioning data corrected 0503
September 2014 Index corrected EB
February 2014 Converted to Danfoss layout-DITA CMS EA
October 2009 to May 2011 Various updates AA through DC
2 | © Danfoss | Jun 2017 11070179 | BC00000068en-US0503
Technical Information
PVED-CX, Series 4 Electrohydraulic Actuator
Contents
Reference
Acronyms used for PVG and PVE................................................................................................................................................ 7
Literature reference for PVG/PVE products.............................................................................................................................8
Standards used for PVED-CX........................................................................................................................................................ 8
Reading guide....................................................................................................................................................................................9
General Information
PVED-CX introduction.................................................................................................................................................................. 10
Overview........................................................................................................................................................................................... 11
PVG functionality
PVG functionality............................................................................................................................................................................13
PVED-CX functionality
PVED-CX functionality..................................................................................................................................................................14
Mechanical subsystem.................................................................................................................................................................14
Housing........................................................................................................................................................................................14
Cable kit........................................................................................................................................................................................14
Mounting.....................................................................................................................................................................................15
Linear Variable Differential Transducer (LVDT)..............................................................................................................15
Spool neutral spring................................................................................................................................................................ 15
Hydraulic subsystem.....................................................................................................................................................................16
Electrical and electronic subsystem........................................................................................................................................16
Communication..............................................................................................................................................................................17
Computerized subsystem...........................................................................................................................................................18
Operational modes........................................................................................................................................................................19
Full operational......................................................................................................................................................................... 19
Hand operational......................................................................................................................................................................19
Automatic system safety integrity self test – ASSIST ..................................................................................................19
Settings..............................................................................................................................................................................................20
Logging..............................................................................................................................................................................................20
Normal operation – self and neighbor supervision concept
Set point command.......................................................................................................................................................................21
Spool supervision...........................................................................................................................................................................21
Solenoid control.............................................................................................................................................................................22
Position reporting..........................................................................................................................................................................22
Neighbor supervision...................................................................................................................................................................22
Microcontroller supervision....................................................................................................................................................... 22
ASIC supervision.............................................................................................................................................................................22
Temperature supervision............................................................................................................................................................22
Power save........................................................................................................................................................................................22
Safety description
POST – Power On Self Test..........................................................................................................................................................23
ASSIST – Automatic System Safety Integrity Test...............................................................................................................23
Runtime fault monitoring........................................................................................................................................................... 23
Communication fault.............................................................................................................................................................. 23
Spool position fault..................................................................................................................................................................23
System data fault...................................................................................................................................................................... 24
Electrical fault.............................................................................................................................................................................24
Temperature fault and correction...................................................................................................................................... 24
Test fault.......................................................................................................................................................................................24
Fault level..........................................................................................................................................................................................24
Fault reaction...................................................................................................................................................................................25
Fault reporting................................................................................................................................................................................ 25
Fault recovery..................................................................................................................................................................................25
Data section
Operational conditions................................................................................................................................................................26
Performance.....................................................................................................................................................................................26
Dimensions and layout................................................................................................................................................................ 26
©
Danfoss | Jun 2017 11070179 | BC00000068en-US0503 | 3
Technical Information
PVED-CX, Series 4 Electrohydraulic Actuator
Contents
Hydraulic data................................................................................................................................................................................. 29
Electrical data.................................................................................................................................................................................. 30
Communication..............................................................................................................................................................................31
LED ................................................................................................................................................................................................31
CAN................................................................................................................................................................................................31
Spool control................................................................................................................................................................................... 32
Spool positioning..................................................................................................................................................................... 32
Closed loop.................................................................................................................................................................................32
Spool monitoring, control and fault reaction.................................................................................................................32
Parameter settings.........................................................................................................................................................................33
Node Id.........................................................................................................................................................................................33
EDS parameters – constants read only............................................................................................................................. 34
EDS parameters – variables read write............................................................................................................................. 34
Error register. Variable read only.........................................................................................................................................35
Conversion of identity parameters to comparable values........................................................................................ 35
Reading guide for product code and serial number....................................................................................................35
Reading guide............................................................................................................................................................................36
Reading guide for numbers .................................................................................................................................................36
Error log. Variables, read only, voilatile.............................................................................................................................36
Error list. Variable read only.................................................................................................................................................. 36
Instantaneous temperature. Variable read only............................................................................................................37
Temperature log....................................................................................................................................................................... 37
Safety Switch status.................................................................................................................................................................37
Safety Relevant Features.............................................................................................................................................................38
Emergency msg. (EMCY)........................................................................................................................................................ 38
EMCY publishing order on CAN bus..................................................................................................................................38
Reset Emergency Message....................................................................................................................................................38
EMCY consumer behavior..................................................................................................................................................... 39
NMT reset application.............................................................................................................................................................39
NMT reset communication....................................................................................................................................................39
Reload Command.....................................................................................................................................................................40
Important Points for PVED-CX Valve Configuration..........................................................................................................40
Changing Node ID using Layer Setting Service.................................................................................................................. 41
Step-1: Switch To Configuration Mode..................................................................................................................................41
Switch To Configuration Mode Global Way....................................................................................................................41
Switch to Configuration Mode Selective Way................................................................................................................41
Step-2: Configure Node ID..........................................................................................................................................................42
Step-3: Store New Assigned Node-ID.....................................................................................................................................42
Step-4: Switch to Normal Mode................................................................................................................................................43
LSS Enquiry Services......................................................................................................................................................................43
Enquire Vendor-ID Command..............................................................................................................................................43
Enquire Product Code Command.......................................................................................................................................43
Enquire Revision Number Command................................................................................................................................44
Enquire Serial Number Command......................................................................................................................................44
Enquire Device Node-ID Command...................................................................................................................................45
EDS access by SDO........................................................................................................................................................................ 45
Set EDS parameter....................................................................................................................................................................45
Set NNI example........................................................................................................................................................................45
Enquire EDS parameter.......................................................................................................................................................... 46
Enquire NNI example...............................................................................................................................................................46
Enquire error log example.....................................................................................................................................................46
Valve Operation..............................................................................................................................................................................47
Normal Operation.....................................................................................................................................................................47
NMT boot up object.................................................................................................................................................................47
Heartbeat Message.................................................................................................................................................................. 47
Getting to Device Mode Active........................................................................................................................................... 48
PVED-CX node 0x21.................................................................................................................................................................48
PVED-CX node NID...................................................................................................................................................................49
Set point.......................................................................................................................................................................................50
4 | © Danfoss | Jun 2017 11070179 | BC00000068en-US0503
Technical Information
PVED-CX, Series 4 Electrohydraulic Actuator
Contents
The Sync message:................................................................................................................................................................... 50
Transmission of PVED-CX Spool Pos. Messages on Sync Msg..................................................................................51
Hand Operational Mode and Full Operational Mode configuration .................................................................... 51
ASSIST.................................................................................................................................................................................................52
ASSIST Pre-Trigger Command............................................................................................................................................. 52
ASSIST Run Command............................................................................................................................................................53
LED by ASSIST ........................................................................................................................................................................... 54
CANCEL ASSIST Command....................................................................................................................................................55
ASSIST Abort Message............................................................................................................................................................ 56
State Machine
Important points about PVED-CX DSM Implementation................................................................................................ 57
INIT state:...........................................................................................................................................................................................57
DISABLED state:.............................................................................................................................................................................. 57
HOLD state:.......................................................................................................................................................................................58
DEVICE_MODE_ACTIVE state:....................................................................................................................................................58
Hand Operational Mode........................................................................................................................................................ 59
Full Operational Mode ...........................................................................................................................................................59
ASSIST Mode ..............................................................................................................................................................................59
FAULT_REACTION state:..............................................................................................................................................................59
FAULT_HOLD state:.......................................................................................................................................................................60
FAULT state:..................................................................................................................................................................................... 60
State Transition...............................................................................................................................................................................60
Limitations and Known Software Issues
Warnings
PVED-CX warnings.........................................................................................................................................................................63
Error codes
Index 1 • Common Name: Reserved........................................................................................................................................64
Index 2 • Common Name: Supply voltage too high..........................................................................................................64
Index 3 • Supply voltage too low..............................................................................................................................................64
Index 4 • Illegal state command................................................................................................................................................65
Index 5 • Division by zero, illegal SW operation..................................................................................................................65
Index 6 • Internal table value corrupted, illegal SW operation......................................................................................66
Index 7 • Wrong data interpretation, truncation of values............................................................................................. 66
Index 8 • Interpolation fault, illegal SW operation............................................................................................................. 67
Index 9 • No handshake to uC....................................................................................................................................................67
Index 10 • Watchdog not starting............................................................................................................................................ 67
Index 11 • RTOS error.................................................................................................................................................................... 68
Index 12 • LVDT verification fault............................................................................................................................................. 68
Index 13 • Neighbor LVDT fault.................................................................................................................................................69
Index 14 •Temperature sensor fault........................................................................................................................................ 69
Index 15 • Fault In RAM................................................................................................................................................................ 69
Index 16 • Temperature average to high...............................................................................................................................70
Index 17 • Code memory check fault...................................................................................................................................... 70
Index 18 • Reserved....................................................................................................................................................................... 71
Index 19 • EEPROM write fault...................................................................................................................................................71
Index 20 • EEPROM content fault..............................................................................................................................................71
Index 21 • EEPROM mirror fault.................................................................................................................................................72
Index 22 • Dead band parameter out of range....................................................................................................................72
Index 23 • Reserved....................................................................................................................................................................... 72
Index 24 • CAN error frame warning........................................................................................................................................73
Index 25 • Signal from master missing................................................................................................................................... 73
Index 26 • Recovered from Bus off...........................................................................................................................................74
Index 27 • Command signal error.............................................................................................................................................74
Index 28 • Reserved....................................................................................................................................................................... 74
Index 29 • Reserved....................................................................................................................................................................... 75
Index 30 • Spool not at set point.............................................................................................................................................. 75
Index 31 • Spool out of neutral..................................................................................................................................................76
©
Danfoss | Jun 2017 11070179 | BC00000068en-US0503 | 5
Technical Information
PVED-CX, Series 4 Electrohydraulic Actuator
Contents
Index 32 • Spool out of neutral at boot up............................................................................................................................76
Index 33 • Electronics to warm..................................................................................................................................................76
Index 34 • CAN spool position from neighbor missing.................................................................................................... 77
Index 35 • Neighbor CAN spool position fault.....................................................................................................................77
Index 36 • No set point.................................................................................................................................................................78
Index 37 • CAN stack error...........................................................................................................................................................78
Index 38 • DSM initialization failed.......................................................................................................................................... 79
Index 39 • A/D converting fault.................................................................................................................................................79
Index 40 • ASSIST. State fault......................................................................................................................................................79
Index 41 • ASSIST. Timing fault..................................................................................................................................................80
Index 42 • Neighbor. Spool out of neutral at boot up.......................................................................................................80
Index 43 • ASSIST. Neighbor reporting fault.........................................................................................................................80
Index 44 • ASSIST. Spool not returned to neutral...............................................................................................................81
Index 45 • ASSIST. Step fault.......................................................................................................................................................81
Index 46 • ASSIST. Neighbor spool does not steer out..................................................................................................... 82
Index 47 • ASSIST. Neighbor spool not returned to neutral............................................................................................82
Index 48 • ASSIST: A port gives to high flow.........................................................................................................................83
Index 49 • ASSIST: B port gives to high flow.........................................................................................................................83
Index 50 • ASSIST: A port gives to low flow...........................................................................................................................83
Index 51 • ASSIST: B port gives to less flow...........................................................................................................................84
Index 52 • Neighbor. Spool out of neutral.............................................................................................................................84
Index 53 • Neighbor. Spool not at set point......................................................................................................................... 85
Index 54 • Neighbor. Spool position reporting fault......................................................................................................... 85
Index 55 • Reference voltage fault........................................................................................................................................... 86
Index 56 • Node ID fault............................................................................................................................................................... 86
Index 57 • EEPROM address fault..............................................................................................................................................86
Index 58 • Error code buffer........................................................................................................................................................87
Ordering
Settings Agreement......................................................................................................................................................................88
Parameter Agreement Template..............................................................................................................................................88
Factory settings for spare part PVED-CX.......................................................................................................................... 88
PVED-CX setting agreement for PVG.................................................................................................................................89
PVED-CX code numbers.............................................................................................................................................................. 90
6 | © Danfoss | Jun 2017 11070179 | BC00000068en-US0503
Technical Information
PVED-CX, Series 4 Electrohydraulic Actuator
Reference
Acronyms used for PVG and PVE
Acronyms Description
ASIC Application Specific Integrated Circuit - the part of the PVE where spool position is controled to
ATEX Certificated for use in explosive environment
AVC Auxillery Valve Comand - ISOBUS/J1939 standard signal for valve control
AVCTO Auxillery Valve Comand Time Out - Fault monitoring setting
AVEF Auxillery Valve Estimated Flow - ISOBUS/J1939 standard signal for valve feedback
CAN Controller Area Network - Communication method used by PVED
CLC Closed Loop Circuit
CRC Cyclic Redundancy Check - Method for ensuring validity of data.
-DI PVE with Direction Indication
DM1 Diagnostic Message 1 - J1939 message informing about present fault
DM2 Diagnostic Message 2 - J1939 message informing about fault history
DM3 Diagnostic Message 3 - J1939 message clearing fault history
DSM Device State Machine. Deterministic description of system process
ECU Electronic Control Unit
EH Electro Hydraulic
-F PVE for Float spool. Two variants: 4 pin with float at 75%. 6 pin with separate float.
FMEA Failure Mode Effect Analysis
ISOBUS Communication standard for CAN
J1939 Communication standard for CAN
LED Light Emitting Diode
LS Load Sensing
LVDT Linear Variable Differential Transducer - Position sensor
NC Normally Closed solenoid valve in PVE
NC-H Normally Closed standard solenoid valve in PVEH
NC-S Normally Closed solenoid valve Super in PVES
NO Normally Open solenoid valve in PVE
PLC Programmable Logical Circuit
®
PLUS+1
POST Power On Self Test. Boot up evaluation for PVED
Pp Pilot Pressure. The oil gallery for PVE actuation
PVB Proportional Valve Basic module - valve slice
PVBS Proportional Valve Basic module Spool
PVBZ Proportional Valve Basic module Zero leakage
PVE Proportional Valve Electric actuator
PVEA PVE variant with 2-6 % hysteresis
PVED PVE variant Digital controlled via CAN communication
PVEH PVE variant with 4-9% Hysteresis
PVEM PVE variant with 25-35% hysteresis
PVEO PVE variant with ON/OFF actuation
PVEP PVE variant PWM controled
PVES PVE variant with 0-2% hysteresis
PVEU PVE variant with US 0-10V
follow setpoint
Trademark for Danfoss controllers and programming tool
©
Danfoss | Jun 2017 11070179 | BC00000068en-US0503 | 7
Technical Information
PVED-CX, Series 4 Electrohydraulic Actuator
Reference
Acronyms Description
PVG Proportional multi-section Valve Group
PVHC PV variant with High Current controlled valve actuator
PVM Proportional Valve Manual control with handle
PVP Proportional Valve Pump side module.Inlet
PVS Proportional Valve end plate
PVSK Proportional Valve end plate crane. Inlet module with Spool Control
PWM Pulse Width Modulation
S4 DJ Series 4 Digital J1939 service tool software for PVED-CC
SAE Society Automotive Engineering
-R PVE with Ramp function
-NP PVE with solenoid disable in Neutral Position
-SP PVE with Spool Position feedback
uC Microcontroller
uCSM Microcontroller State Machine
U
DC
U
S
Power supply Direct Current; also called V
Steering voltage for the PVE control; also called V
for battery voltage
bat
S
Literature reference for PVG/PVE products
Literature reference
Literature title Type Order
PVG 32 Proportional valve group Technical Information 520L0344
PVG 100 Proportional valve group Technical Information 520L0720
PVG 120 Proportional valve group Technical Information 520L0356
PVG 32 Metric ports Technical Information 11051935
PVED-CC Electro-hydraulic actuator Technical Information 520L0665
PVED-CX Electro-hydraulic actuator Technical Information 11070179
Basic module for PVBZ Technical Information 520L0721
PVSK module with integrated diverter valve and P-disconnect function Technical Information 520L0556
PVPV / PVPM pump side module Technical Information 520L0222
Combination module PVGI Technical Information 520L0405
PVSP/M Priority module Technical Information 520L0291
Standards used for PVED-CX
International Organization for Standardization:
•
ISO 11898-2 Road vehicles, CAN, Part 2, High-speed medium access unit (physical layer)
‒
ISO 13766:2006(E) Earth moving machinery, Electromagnetic compatibility
‒
ISO 13849 Safety of Machinery
‒
CAN in Automation:
•
CiA 3.01 v4.02 CANopen protocol.
‒
CiA 4.08 v1.51 Device specific protocol for proportional valves.
‒
IEC 61508
•
number
8 | © Danfoss | Jun 2017 11070179 | BC00000068en-US0503
Technical Information
PVED-CX, Series 4 Electrohydraulic Actuator
Reference
Reading guide
Sections Overview and section PVG functionality give a general description of the PVG to give basic
•
domain knowledge.
Section PVED-CX functionality is a thorough description of PVED-CX subsystems and their interaction.
•
Sections Normal operation – self and neighbor supervision concept on page 21 and section Safety
•
description on page 23 are thorough descriptions of control, monitoring, safety features and
behaviors.
Section Data details for application engineers.
•
Section PVED-CX warnings lists warnings relevant to the PVED-CX.
•
Section Error codes is a walkthrough of module error codes, potential cause and counter action.
•
Section Ordering shows the ordering guidelines.
•
©
Danfoss | Jun 2017 11070179 | BC00000068en-US0503 | 9
Technical Information
PVED-CX, Series 4 Electrohydraulic Actuator
General Information
PVED-CX introduction
The Danfoss PVED-CX is a PVE-Series 4 actuator for the PVG 32.
CX is an abbreviation for CAN bus communication and eXtended safety.
The PVED-CX is intended for markets where a documented extended safety is needed. In particular
cranes, man-lifts and telehandlers are in focus.
A PVG with PVED-CX is designed to meet Safety Integrity Level 2 (SIL2). So when performing a Risk and
Hazard Analysis, as mandated by the EU Machinery Directive 2006/42/EC, the Danfoss customer can cut
down on external safety systems and easier get an IEC61508 certified system.
A product specific wiring harness is part of the PVED-CX concept as use of the special Danfoss end plate
for cranes (PVSK) is.
Certification of the PVED-CX system appliance to the IEC61508 is made by TÜV SÜD, Munich, Germany.
PVG with PVED-CX
PVED-CX, front view PVED-CX, back view
10 | © Danfoss | Jun 2017 11070179 | BC00000068en-US0503
W
W
Technical Information
PVED-CX, Series 4 Electrohydraulic Actuator
General Information
Warning
Please work through all warnings before implementing actuators in any application. The list of warnings
must not be seen as a full list of potential dangers. Depending on application and use other potential
dangers can occur.
Warning
All brands and all types of directional control valves – including proportional valves – can fail and cause
serious damage. It is therefore important to analyze all aspects of the application. Because the
proportional valves are used in many different operation conditions and applications, the machine
builder/ system integrator alone is responsible for making the final selection of the products – and
assuring that all performance, safety and Warning requirements of the application are met.
Overview
The PVG is a sectioned spool valve stack with up to 12 individually controlled proportional valves. With
the PVED-CX the PVG can operate as one or more control sections.
A control section is a group of two to eight PVED-CX connected by one cable kit with mutual monitoring
and the feature that any PVED can bring the entire control section to safe state if a fault is found.
The oil flow out of the work section (A- or B-port) can be controlled by a combination of the following:
PVED-CX controlling the spool position using pilot oil pressure.
•
A handle (PVM) in mechanical interface with the spool.
•
The oil flow into the PVG can be controlled using an electrically controlled main oil valve (PVSK) as
•
end cover. The PVED-CX is foreseen as PVSK controller in the Danfoss SIL2 concept. The PVSK can also
supply an additional PVG via the High Pressure Carry Over (HPCO) port.
PVED-CX functionalities – block diagram
1 – Neutral springs
2 – Solenoids
3 – PVG with PVED-CX
4 – Safety switch
6 – Electronics
7 – Power for solenoids
8 – Analog neighbor information
9 – Neighbor surveillance can cut the oil flow
©
Danfoss | Jun 2017 11070179 | BC00000068en-US0503 | 11
Technical Information
PVED-CX, Series 4 Electrohydraulic Actuator
General Information
5 – Emergency 10 – Set points and feedback
The PVED-CX uses the CANopen protocol, thus following the standard protocol CiA301v402 and the
device specific protocol for proportional valves CiA408v151 with a minimum set of vendor specific
additions.
The physical layer for CAN communication applies to ISO 11898-2 high speed CAN.
The spool is controlled by spool position with 127 positions each direction and dead band compensation.
Monitored manual operation is possible.
Electronics and spool control are independently power supplied and the redundant system monitoring
can shut down the whole control section in case of failures.
The redundant monitoring continuously evaluates spool position, communication, electronics, memory,
calculations and temperature.
To avoid needless power consumption the PVED-CX has the Power Save feature, where power
consumption is reduced by almost 90% when the spool is in neutral.
PVG 32 with PVED-CX overview, PVE option mounted
12 | © Danfoss | Jun 2017 11070179 | BC00000068en-US0503
V310072.A
PVE
Electronics
NC Solenoid valve
Pilot oil supply
B port
Oil
A port
PVB
PVM
Neutral spring
PVBS
NO solenoid valve
LVDT
<- Retract towards PVE
Extend away from PVE ->
P -> A
Technical Information
PVED-CX, Series 4 Electrohydraulic Actuator
PVG functionality
PVG functionality
This chapter will give an overview of the PVG functionality.
Valve section with naming - standard mounted - seen from PVP
The PVG valve distributes oil from pump flow to a particular work function in the application via a specific
valve section. This is done by moving the spool (PVBS).
Depending on the choice of components the oil work flow enters the PVG through the PVP (proportional
valve pump side module) or the PVSK (proportional valve end plate for crane) and enters the PVB
(proportional valve basic module) via the P gallery and leaves through the T gallery.
When looking at figure 4 you see the valve section from PVP towards PVSK with the PVM and PVE
standard mounted. When PVM and PVE are interchanged it’s called option mounted.
With the spool in neutral, where it is kept by the neutral spring, the connection to the application via
ports is blocked.
Moving the spool towards the PVE, as in figure 4, opens a connection between P and A and also between
B and T. This is done by either pushing the PVM or sending a retract command to PVED. The PVED move
the spool by letting Pilot Oil Pressure (Pp) push on the right end of the PVBS and releasing pressure from
the left end. For details on PVG32 please see PVG 32 Proportional valves, Technical information, 520L0334.
Any PVG with PVM can be operated by PVM alone independent of power supply. Any PVG with PVED-CX
can monitor PVBS if power and communication conditions are present.
©
Danfoss | Jun 2017 11070179 | BC00000068en-US0503 | 13
V310078.A
Oil pressure
Solenoids
Poppet valve
Function
Control
Communication
ASIC
LVDT
Closed loop
Set point via CAN
PWM
Analogue reporting
CAN reporting
LED status
CAN signal acceptance
Message sanity
Hand shake - component sanity
Memory check
Calculation vs execution
Redundant calculation
Component environment
Logging
Ignore input
Deactivate solenoids
Deactivate all modules in section
CANbus reporting
Logging
LED setting
Reaction
Safety
System controller
Neighbor module
PVED-CX section
Spool
Application hydraulic system
Application electrical system
Monitoring
PVED-CX
Technical Information
PVED-CX, Series 4 Electrohydraulic Actuator
PVED-CX functionality
PVED-CX functionality
This section has focus on how the PVED-CX works and interacts. Understanding of this must be regarded
as a pre-condition for understanding module settings and system operation.
The PVED-CX is a mechatronic device, meaning a mechanical, a hydraulic, an electric, an electronic and a
computer system interacting with external mechanical, hydraulic, electrical, electronic and computerized
systems.
PVED-CX mechatronical interaction
Mechanical subsystem
Housing
The housing of the PVED-CX protects the internal parts from the environment and gives by design the
14 | © Danfoss | Jun 2017 11070179 | BC00000068en-US0503
optimal interface to cabling, Pilot pressure and spool.
Cable kit
A special cable kit has been designed for the PVED-CX making it possible to operate in control sections of
two to eight modules with neighbor monitoring.
The cable has five incoming wires:
•
•
•
•
•
CAN high signal wire
CAN low signal wire
V
V
Ground
for electronic power supply
bat
for solenoid power supply
bat2
System
Controller
Vbat
Vneg
CAN_H
CAN_L
Vbat2
CAN_H
Cable harness
Cable harness
PVED-CX #1 PVED-CX #2 PVED-CX #n
Cable harness
LVDT out
LVDT in
Vbat2 out
Vbat2 in
Vbat3
CAN_L
CAN_H
Vneg
Vbat
LVDT out
LVDT in
Vbat2 out
Vbat2 in
Vbat3
CAN_L
CAN_H
Vneg
Vbat
LVDT out
LVDT in
Vbat2 out
Vbat2 in
Vbat3
CAN_L
CAN_H
Vneg
Vbat
120 ohm
V310008.B
W
W
Technical Information
PVED-CX, Series 4 Electrohydraulic Actuator
PVED-CX functionality
Cable kit principle
Three wires are added between the modules:
1. V
power supply. This wire is looped as a V
bat2
through the safety switches in the modules.
2. V
power supply is a transformation of V
bat3
the solenoid valves.
3. LVDT out – LVDT in signal wire. This connects the analogue spool position signal from one module
to the neighbor microcontroller.
The termination in the last connector is optional.
out – V
bat2
out from the last module and now used for powering
bat2
in between the modules and goes
bat2
Mounting
The Danfoss PVG concept is based on parts interchangeability. This is also valid for the PVED-CX and
makes field retrofitting possible.
PVED can be mounted on both ends of PVB.
•
Cable kit can be mounted with first or last connector next to PVP.
•
Cable kit can be delivered with and without CANbus termination.
•
Warning
Deviation from recommended torque can harm performance and module.
Linear Variable Differential Transducer (LVDT)
The Linear Variable Differential Transducer (LVDT) or position sensor is the interface between the
mechanical system (spool) and the electronic system.
Warning
The LVDT must never be mechanically adjusted, bent, damaged or partially blocked as this will lead to
incorrect information on spool position.
Spool neutral spring
The PVBS neutral spring is an important safety component as it keeps or moves the PVBS in blocked
position when solenoid valves are disabled. The spring will keep the A and B port closed as long as the
differential pressure is below 6 bar.
©
Danfoss | Jun 2017 11070179 | BC00000068en-US0503 | 15
Pp
NC3
NC1
Spool
NO4
NO2
Tank
LVDT
Set point
V310073.A
1.0 [0.039]
Electronics
W
Technical Information
PVED-CX, Series 4 Electrohydraulic Actuator
PVED-CX functionality
Hydraulic subsystem
The hydraulic subsystem is used for moving the spool and thereby opening the valve for work flow.
Pilot oil diagram
Electrical and electronic subsystem
The heart of the hydraulic subsystem is the solenoid valve bridge. It consist of four poppet valves, the two
upper ones are normally closed (NC-S) with a small bleed, the two lower ones are normally open (NO).
The Pp will work against the PVBS neutral spring when the spool is moved out of blocked (neutral) and
together with the spring when going in blocked. This combined with a larger opening in the NO than in
the NC-S will give a faster movement towards blocked than out of blocked.
Warning
Obstacles for the Pp can have direct influence on spool control. Reduced pilot pressure will limit spool
control. Too high Pp can harm the system.
The PVED-CX is based on the known PVED-CC series 4 technology with the ASIC core controlling the main
functionality of the solenoid valves, and a micro-controller system as Module Safety Manager and
interface between the analogue ASIC and the CAN bus communication. The micro-controller also
monitors its neighbor PVED-CX and has the ability to disable spool actuation for the whole control
section.
16 | © Danfoss | Jun 2017 11070179 | BC00000068en-US0503
Safety
switch
Controller
Analogue
Control
Solenoid
Valves
Main Spool
Position
sensor
Cable harness
CAN
Spool Set-point
Closed loop
feed back
LVDT out to neighbor B
LVDT in
from
neighbor A
Spool position
Solenoid valve
control
Vbat3
Vbat2 in
Vbat2 out
Pilot oil
pressure
build up
Mech linkage.
Solenoid valve
enable
Safety
switch
Controller
Analogue
Control
Solenoid
Valves
Main Spool
Position
sensor
Cable harness
CAN
Spool Set-point
Closed loop
feed back
LVDT out to neighbor B
LVDT in
from
neighbor A
Spool position
Solenoid valve
control
Vbat3
Vbat2 in
Vbat2 out
Pilot oil
pressure
build up
Mech linkage.
Solenoid valve
enable
Neighbor A
Neighbor B
Safety
switch
Controller
Analogue
Control
Solenoid
Valves
Main Spool
Position
sensor
Cable harness
CAN
Spool Set-point
Closed loop
feed back
LVDT out to neighbor B
LVDT in
from
neighbor A
Spool position
Solenoid valve
control
Vbat3
Vbat2 in
Vbat2 out
Pilot oil
pressure
build up
Mech linkage.
Solenoid valve
enable
V310 207.A
Technical Information
PVED-CX, Series 4 Electrohydraulic Actuator
PVED-CX functionality
Function blocks for electronics
Controller: The build in micro-controller.
Safety switch: MOSFET for collective solenoid disabling inside the control section.
Position sensor: Mechanical electrical interface.
Analogue control: A closed loop control of spool position based on set point. Feedback to system is actual spool
position and error state.
Communication
©
Danfoss | Jun 2017 11070179 | BC00000068en-US0503 | 17
The PVED-CX has three methods of communication.
Optical from module
•
Analogue one way communication
•
Digital two way communication
•
NOT_READY
INIT
FAULTDISABLED
HOLD
FAULT_HOLD
DEVICE_MODE_
ACTIVE
FAULT_
REACTION
Operational
Pre-Operational
Stopped
Communication state machine
Initialisation
Reset
Application
Reset
Communication
Initialising
Device state machine
Power on
V310034.A
Technical Information
PVED-CX, Series 4 Electrohydraulic Actuator
PVED-CX functionality
Optical – LED
Blinking and steady light is implemented to facilitate maintenance and application engineering.
Analogue
Analogue communication is implemented.
An analogue signal is sent from active module to monitoring module to enforce redundancy.
Module under surveillance is referred to as neighbor module in settings.
The operational mode of the module under surveillance (neighbor) decides the behavior of the
monitoring module.
Digital – CANopen
The CANopen communication is the main method. It is used for:
•
Control of module by master. Master defines state transition and set points.
•
Reporting from module to master. Module reports spool position and safety violation
•
Setting in module by master. Some parameters can be changed.
•
Inquiry from master to module.
Computerized subsystem
CANopen is a communication protocol defined by the society CAN in Automation (CiA). For details in the
protocol we refer to CiA.
The PVED-CX operates according to defined Device State Machines (DSM) giving conditions for transition
between states. The Communication State Machine (CSM) is pre-condition for the DSM.
State transitions depends on internal conditions e.g. the sanity of the PVED-CX and can also depend on
external conditions e.g. application controller commands and changes in preconditions for normal valve
operation.
DSM and CSM for PVED-CX
18 | © Danfoss | Jun 2017 11070179 | BC00000068en-US0503
Technical Information
PVED-CX, Series 4 Electrohydraulic Actuator
PVED-CX functionality
When power is applied to the PVED-CX it will initialize components and validate component states and
parameter settings. This is the power on self test (POST).
If test is passed the PVED will enter Disabled State and make it self known to the controller as active.
Otherwise it will enter Fault mode and if possible also generate a fault message.
When the state is Device Mode Active or Device Mode Disabled module reporting can be trusted when in
fault states report validity is related to the fault type.
Operational modes
The PVED-CX has three accessible operational modes for normal operations.
Full operational. Spool position is controlled and monitored. Device Mode Active.
•
Hand operational. Spool position is monitored. Device Mode Disabled.
•
Automatic system safety integrity self test. Device Mode Active.
•
It is not mandatory for all modules in the same Control Section to be in the same Operational Mode.
Fault monitoring is active independent of operational mode.
See Safety description on page 23 section.
Full operational
In full operational mode the PVED-CX controls the spool and monitors the neighbor spool.
This mode is characterized by:
Set point is received from Master and acted on by the module
•
Solenoid valves are enabled by local switch if not in Power Save
•
Neighbor monitoring of set point and spool position is active
•
Spool position reporting is active
•
No fault is present
•
LED green
•
Hand operational
In hand operational mode the PVED-CX cannot control the spool.
This mode is characterized by:
Spool position is defined by PVM and spool neutral spring
•
Set point is not calculated. Master module does not have to send
•
Solenoid valves are disabled by local switch
•
Neighbor monitoring of spool reporting is active
•
Spool position reporting is active
•
No fault is present
•
LED green.
•
Automatic system safety integrity self test – ASSIST
The ASSIST is as a tool for end-of-line test and maintenance test especially in connection with parts
replacement and system modification.
In the ASSIST the system ability to recognize spool movement as fault and signal incongruence is tested
automatically. This also includes the redundancy created by the cable harness.
The following is tested:
©
Danfoss | Jun 2017 11070179 | BC00000068en-US0503 | 19
Technical Information
PVED-CX, Series 4 Electrohydraulic Actuator
PVED-CX functionality
Main spool kept in and brought back to neutral by spring
•
The 4 magnetic solenoids
•
The LVDT sensor
•
The ASIC spool position reporting
•
The ASIC closed loop control of the main spool position
•
Node Id and neighbor node Id validity
•
This mode is characterized by:
Solenoid valves are activated but not controlled by master device
•
Fault monitoring and reporting has a mode specific pattern
•
Settings
The PVED-CX offers a number of settings for both system information and system operation. The
parameters are, as required in CANopen, organized in an Electronic Data Sheet (EDS). The available
parameters are both fixed parameters and variable parameters. For details in the protocol we refer to CiA.
Logging
During operation the PVED-CX logs data, that can be accessed at any time.
Error history. A runtime log, cleared by reset and power off, keeps track of error order in a FIFO buffer
•
Error counts. For each error code an occurrence counter is maintained in the EEPROM
•
Temperature (current)
•
Temperature histogram. For every 6 minutes of run time the current temperature is logged
•
Please find details in the Data section.
20 | © Danfoss | Jun 2017 11070179 | BC00000068en-US0503
Safety
switch
Controller
Analogue
Control
Solenoid
Valves
Main Spool
Position
sensor
Cable harness
CAN
Spool Set-point
Closed loop
feed back
LVDT out to neighbor B
LVDT in
from
neighbor A
Spool position
Solenoid valve
control
Vbat3
Vbat2 in
Vbat2 out
Pilot oil
pressure
build up
Mech linkage.
Solenoid valve
enable
Safety
switch
Controller
Analogue
Control
Solenoid
Valves
Main Spool
Position
sensor
Cable harness
CAN
Spool Set-point
Closed loop
feed back
LVDT out to neighbor B
LVDT in
from
neighbor A
Spool position
Solenoid valve
control
Vbat3
Vbat2 in
Vbat2 out
Pilot oil
pressure
build up
Mech linkage.
Solenoid valve
enable
Neighbor A
Neighbor B
Safety
switch
Controller
Analogue
Control
Solenoid
Valves
Main Spool
Position
sensor
Cable harness
CAN
Spool Set-point
Closed loop
feed back
LVDT out to neighbor B
LVDT in
from
neighbor A
Spool position
Solenoid valve
control
Vbat3
Vbat2 in
Vbat2 out
Pilot oil
pressure
build up
Mech linkage.
Solenoid valve
enable
V310 207.A
Technical Information
PVED-CX, Series 4 Electrohydraulic Actuator
Normal operation – self and neighbor supervision concept
The main spool is kept in blocked/neutral position by the neutral spring. By use of the handle (PVM) or
the solenoid valves and the Pp the spool can be moved to any position and so open for system pressure
to the application.
Function cooperation in control section
Set point command
Spool supervision
©
Danfoss | Jun 2017 11070179 | BC00000068en-US0503 | 21
The Set Point for the PVED is broadcasted on CAN bus by the System Main Controller/Master. During
transmission the signal is evaluated for irregularity by all modules on the bus but only modules
programmed for the specific signal will perform further calculations.
Upon reception the micro-controller (relevant module and neighbor) evaluates the validity of the set
point.
If the set point is valid, and not blocked when power save is active, a local switch in the ASIC is conected
by the microcontroller and the solenoid valves are enabled.
The controller transforms the digital message to a PWM signal and sends it to the ASIC.
The ASIC evaluate if the PWM is in the valid range.
At any time the ASIC monitors the spool position via the position sensor (LVDT) feedback. This
determines the spool position for the closed loop control. Additionally the spool position is sent from the
Technical Information
PVED-CX, Series 4 Electrohydraulic Actuator
Normal operation – self and neighbor supervision concept
ASIC to the neighbor microcontroller as an analogue signal and the LVDT feedback is also fed to the
microcontroller for generation of the CAN message.
Solenoid control
Based on set point and spool position the ASIC performs a closed loop control at a fixed frequency
controlling the solenoid bridge.
Position reporting
The PVED-CX sends, when operating as a system configured module, continued spool position reports.
This is intended as information for comparison for the application controller and the neighbor module
Neighbor supervision
Microcontroller supervision
ASIC supervision
CAN: Spool position is calculated and broadcasted on the CAN bus with redundant representation of data.
Spool position is reported as blocked when closer to neutral than approx. 0.7 mm.
Spool position is reported as not blocked when further from neutral than approx. 0.7 mm.
When the spool is further from neutral than software dead-band threshold the spool position is
calculated as an averaged value over the last 50 ms.
Analogue: Spool position is sent as an analogue signal to neighbor microcontroller.
The special PVED-CX cable kit ensures that the supervising module has the spool position from the
supervised module as an analogue value and also the reported spool position via CAN bus. If supervised
module is in Full Operational mode the set point from the controller is also known.
The neighbor microcontroller compares the analogue and the CAN spool position values. In Full
Operational Mode the spool position is also compared to the set point. Any deviation will raise an error.
Spool monitoring in PVG, see Cable kit principle.
The microcontroller has mutual watch dog functionality with a PIC giving redundant ability to shut down
the ASIC. The PIC can also shut down CAN communication.
The ASIC feeder signal for the LVDT is monitored by the microcontroller.
Temperature supervision
The temperature of the electronic printed circuit board (PCB) is continuously monitored. This has two
purposes:
Calculated expected system reaction time must reflect temperature changes in oil viscosity.
•
Component temperature conditions are within specified values.
•
Power save
To minimize energy consumption the PVED-CX has a power save functionality. If the set point for the
PVED-CX has been blocked for more than 500ms the solenoids will be deactivated by the local switch.
This reduces power consumption by 90 %.
22 | © Danfoss | Jun 2017 11070179 | BC00000068en-US0503
Technical Information
PVED-CX, Series 4 Electrohydraulic Actuator
Safety description
The Danfoss definition of safe state transition by fault is: Spool is placed in blocked position (neutral).
The PVED-CX has Active Fault Reaction, e.g. brings the system into a safe state on fault.
The PVED-CX safety concept is based on three elements:
POST – Power On Self Test
•
ASSIST – Automatic System Safety Integrity Test
•
Runtime fault monitoring and reaction
•
The basic elements for product safety are:
Continuous module monitoring
•
Fault recognition and reaction
•
Fault reporting and recording
•
Fault recovery
•
POST – Power On Self Test
Passing of the Power On Self Test is a pre condition for Full Operational Mode and ASSIST.
The POST evaluates internal signals, memory state, internal settings and neighbor connection.
ASSIST – Automatic System Safety Integrity Test
The Automatic System Safety Integrity Self Test evaluates the electrical wiring connections, module inter
communication, spool monitoring and hydraulic spool control.
The ASSIST is an optional test but must be passed in case of:
First time use of PVG
•
Changes in settings
•
Cable kit replacement and manipulation
•
Module replacement
•
Runtime fault monitoring
The fault monitoring is a part of the continuous self and neighbor monitoring. A number of conditions
will force the Device State Machine transition to fault mode. For details see sections: Data section and
Error codes.
Communication fault
Communication faults interrupts application (system) and module cooperation. These faults are mainly
connected to wiring faults, disabled controllers and illegal commands.
Loss of communication
•
Valid communication with invalid data
•
Communication disturbance
•
The CAN communication is based on a physical layer applying to ISO 11898-2 high speed CAN. Faults
handled by this standard are not considered relevant for this document with recovery from bus off as an
exception.
Spool position fault
Spool position faults are directly related to the hydraulic performance of the application. These faults
indicate difference between demanded and actual spool position.
The following categories of position faults are recognized:
©
Danfoss | Jun 2017 11070179 | BC00000068en-US0503 | 23
Technical Information
PVED-CX, Series 4 Electrohydraulic Actuator
Safety description
Spool further out than demanded.
•
Spool in opposite direction to demanded.
•
Spool not in neutral: Target window monitoring
•
The spool position is determined by LVDT contact to spool end. LVDT faults are treated as electrical faults.
Spool position is handled with tolerance as stated in Data section with consideration to mechanical delay
and temperature influence.
System data fault
The data handling is depending on the quality of stored data and the range of input data. To avoid faults
the following is monitored:
Degradation of EEPROM.
•
Degradation of FLASH.
•
Sanity of look up tables
•
Undefined calculations – division by 0
•
Interpolation replaced by extrapolation
•
Unwanted truncation
•
Interrupted write process - Data mirror
•
Inconsistency in spool position calculation
•
Electrical fault
The quality/presence of the following electrical signals is monitored to guarantee behavior within
specification.
Reciprocal watch dog signals between PIC and microprocessor
•
Battery voltage in specified level
•
LVDT feeder signals from ASIC
•
Analogue to digital converter ADC
•
PWM (Pulse width Modulated) signal from micro processor to ASIC
•
Temperature fault and correction
Electronic component reliability and electronic component life time are influenced by temperature as
well as oil viscosity is. Temperature measurements on PCB is used for
Interrupting spool control if PCB temperature is to high
•
Interrupting spool control if PCB average temperature is to high
•
Delay spool monitoring time out if PCB temperature is to low
•
Determine product work hours based on temperature histogram
•
Test fault
The PVED has two tests with special status.
POST. Power On Self Test for module integrity before operation.
•
ASSIST. Automatic System Safety Integrity Self Test for module cooperation in control section.
•
Fault level
The PVED-CX has three fault severity levels.
24 | © Danfoss | Jun 2017 11070179 | BC00000068en-US0503
Technical Information
PVED-CX, Series 4 Electrohydraulic Actuator
Safety description
Warning
•
Critical
•
Severe
•
Warning
Warning is entered if the fault is expected to have external origin and the PVED performance is certain
not to suffer once the state is passed. Warning has no influence on neighbor modules activity.
Critical
Critical is entered if reliability of a defined element of the system could be threatened. Critical has
influence on neighbor modules activity.
Severe
Severe is entered if system reliability could be threatened. Severe has influence on neighbor modules
activity.
Threshold not passed
If a fault precondition is present the PVED keeps track but operates as requested until an eventual
threshold is passed e.g. spool not at demanded position but only for a short time.
For every fault related to a time or occurrence threshold a counter is established.
The counter is started and reset according to a fault depending scheme.
Fault reaction
Fault reporting
The fault reaction has highest priority in the PVED-CX. Depending on the fault the PVED immediately
goes into a defined fault state. Any fault of a higher severity will override any present less severe fault.
Warning Local switch is disabled. Solenoid valves disabled.
Critical and
Severe
Spool monitoring and reporting still active. Comparison set point-actual position is disabled
Fault monitoring still active depending on operation mode.
Neighbor monitoring still active
Safety switch is disabled. Solenoid valves disabled in the whole control section.
Spool monitoring and reporting still active. Comparison set point-actual position is disabled
Fault monitoring still active depending on operation mode.
Neighbor monitoring still active
Fault reporting is a part of the communication task and has lower priority than fault reaction.
CAN bus Appropriate emergency messages are sent out according to the CANopen standard.
Error logs Fault is stored in an EDS log in RAM over last 50 errors using a first in first out buffer.
Light emitting diode To ensure easy maintenance the PVED-CX utilizes the LED to indicate state of the
In case of multiple errors Servere has precedence over Critical that has precedence over
Warning. Errors of same severity are broadcast in order of occurrence.
Fault is stored in an EDS log in EEPROM showing occurrence of every fault Id. Max 255.
The Error log in the EEPROM cannot be reset.
module.
Fault recovery
Module and system fault recovery requires that all faults have disappeared.
Warning Recovery is possible with software reset command.
Critical Recovery is possible with software reset command.
Severe Recovery is only possible with power cycle.
©
Danfoss | Jun 2017 11070179 | BC00000068en-US0503 | 25
5 SP_POS_IN
4 not connected
2 Vbat2 IN
1 Vbat2 OUT
10 SP_POS_OUT
9 CAN_L
8 CAN_H
7 Vneg
6 Vbat
3 Vbat 3
LED
V310 021.A
Technical Information
PVED-CX, Series 4 Electrohydraulic Actuator
Data section
Operational conditions
The PVED-CX will only operate according to this table.
Operational conditions
Mode Supply
Electronic test. POST Mandatory Optional Optional Optional
System test. ASSIST Mandatory Mandatory Mandatory Disabled
Manual operation Optional
Full operation Mandatory Mandatory Mandatory Mandatory
*
Mandatory if spool position information is requested.
**
If hydraulic performance is expected.
A pre-condition for electrical performance according to this technical information is interconnection of
the PVED-CX in control sections. A control section is two to eight PVED-CX connected by a cable kit.
Danfoss defines safe state as spool set to blocked/neutral position.
Power CAN control Pilot oil pressure Oil main pressure
*
Optional
*
Optional Mandatory
**
**
Performance
Dimensions and layout
Reaction time for actuation
Function @ 21 cSt @ 13,3 bar Solenoids Time
Reaction time, neutral to max spool travel Powered Min 50 ms / Max 200 ms
Reaction time, max spool travel to neutral Powered Max 150 ms
Reaction time, power on to max spool travel Powered Min 1000 ms / Max 4000 ms
Reaction time, max spool travel to neutral Disabled Max 175 ms
Power up, from power on to CAN active 1000 ms (up to 1250 ms by unstable
power supply)
ASSIST run time per module 4 seconds
Hysteresis @0.02Hz Typ 0% / Max 1%
Oil viscosity: 21.0 ± 0.5 cSt, Pilot. Pilot pressure (P-T): 13.3 ±0.5 bar.
Connector pin out
26 | © Danfoss | Jun 2017 11070179 | BC00000068en-US0503
J0
J1
J2
Jn
Jn Strip + Wirequard 51418
2 x 1.5 mm2 + 3 x 0.75 mm2 Roboslepp
8 x 0.75 mm2 Roboslepp
Long cable 4000 ±50 mm / Short cable 1000 ±50 mm
135
Marking Part No. + prod. week-year
V310192.B
W
J0
J1 J2 J3 J4 J6 J7J5
V310199.B
Technical Information
PVED-CX, Series 4 Electrohydraulic Actuator
Data section
Cable dimensions
Long cable kit (4000 mm) is without CAN bus termination.
Short cable kit (1000 mm) is with 120 Ohm CAN bus termination in connector Jn.
Warning
Cable is specific designed for use with PVED-CX. When handling cable at temperature below 0°C [32°F]
avoid twisting and rough handling.
Cable color codes and external connection
Description J0 / wire ends J1 J2 Jn
*
CAN low
Yellow 9 9 9
CAN high Orange 8 8 8
Ground Brown 7 7 7
Vbat Red 6 6 6
Vbat 2 Green 2 – –
*
CAN wires are only intended for communication according to ISO 11898-2.
PVED-CX with cable kit
©
Danfoss | Jun 2017 11070179 | BC00000068en-US0503 | 27
Cable can be mounted with J1 as the rightmost.
100.3 [3.95]
69.5 [2.74]
25.0 [0.98]
V310033.A
102.6 [4.04]
92.7 [3.65]
23.6 [0.93]
118.4 [4.66]
106 [4.17]
55.3 [2.18]
24.5 [0.97]
Technical Information
PVED-CX, Series 4 Electrohydraulic Actuator
Data section
Neighbor guide
Node connector J1 J2 J3 ... Jn
Neighbor connector Jn J1 J2 ... Jn-1
Example
Node Id 20 21 22 ... 26
Neighbor node Id 26 20 21 ... 25
Cable kit specification
Voltage - V
Power Maximum 80 W
Grade of enclosure - version with AMP JPT connector IP 66
Ambient temperature Use -30 °C → +90 °C
bat
, V
bat2
Maximum 36 V
[-22 °F → +194 °F]
Storage -40 °C → +100 °C
[-40 °F → +212 °F]
Recommended long time storage
conditions in packaging
+10 °C → +30 °C
[50 °F → +86 °F]
PVED-CX dimensions, mm [in]
28 | © Danfoss | Jun 2017 11070179 | BC00000068en-US0503
Loading...