Bosch Rexroth 4WS2EM 10 Series User manual

Explosion-proof
hydraulic valves
Type 4WS2EM 10...VH1...-100
Operating instructions
RA 29583-VH1-100-B0/05.12
Replaces: 05.10
Material Number
R901272980

1/14
Servo directional control valve
of 4-way design
Type 4WS2EM...VH1...-100
Nominal size 10
Unit series 5X
Maximum working pressure 315 bar
Maximum flow rate 180 l/min
RA 29583-VH1-100-B1/05.12
Replaces: 05.10
Information on explosion protection:
Ranges of application in accordance with Article 505, NEC ®
– IS Class I, Zone 0, AEx ia IIC T4
– NI Class I, Zone 2
– Ambient temperature range –20 °C ≤ Ta ≤ +60 °C
For potentially explosive atmospheres
Part I Technical Data Sheet
What you need to know about these Operating Instructions
These Operating Instructions apply to the explosion-proof version of Rexroth valves,
and consist of the following three parts:
Part I Technical Data Sheet RA 29583-VH1-100-B1
Part II Product-specific Instructions RA 29583-VH1-100-B2
Part III Control drawing RA 29583-VH1-100-B3
You can find further information on the correct handling of Rexroth hydraulic products in our publication
“General product information for hydraulic products”, RE 07008.
RA 29583-VH1-100-B0


H5893•_d

2/14 Bosch Rexroth AG Hydraulics 4WS2EM...VH1...-100 RA 29583-VH1-100-B1
Overview of Contents
Contents Page
Features 2
Ordering data and scope of delivery 3
Symbol 3
Function, sectional diagram 4
Technical data 5 and 6
Information on explosion protection 6
External trigger electronics 6
Plug-in connector 7
Electrical connection 7
Characteristic curves 8 to 11
Unit dimensions 12
Flushing plate 13
Features
– Servo directional control valve for proper use in potentially
explosive atmospheres of Zone 0
– Valve for closed-loop position, force and speed control
– 2-Stage servo valve with mechanical feedback
– 1st stage in the form of flapper nozzle amplifier
– For subplate mounting,
Mounting hole configuration to
ISO 4401-05-05-0-05 with ports X and Y.
Subplates, see page 12
– Dry servo motor, no contamination of solenoid gaps by
pressure fluid
– Non-wearing spool return element
– Actuation:
External trigger electronics in modular form, additional
safety barriers (order separately), see Page 6
– Valve is calibrated and tested
– Internal/external control oil supply and return individually
orderable
– Spool with flow force compensation
– Control sleeve permanently centered, therefore reducing
sensitivity to temperature and pressure
– Pressure chamber gaps on control sleeve sealed,
no wear to O-rings
– Filter for 1st stage freely accessible from the outside

Hydraulics Bosch Rexroth AG
RA 29583-VH1-100-B1 4WS2EM...VH1...-100 3/14
Ordering data and scope of delivery
Symbol
1) Nominal flow rate
The nominal flow is based on a 100 % setpoint signal at a
valve pressure drop of 70 bar (35 bar per metering edge).
The flow can be affected by other values.
A possible nominal flow tolerance of ± 10 % (see flow sig-
nal function on page 8) must be taken into consideration.
2) Electrical triggering data
The control signal must be generated by a current-regulat-
ed output stage with superimposed dither signal. For trigger
electronics (servo amplifiers), see page 6.
3) Control oil
The pilot pressure should be kept as constant as possible.
Therefore, external pilot control via port X can be advanta-
geous. The valve may be operated with higher pressure at
X than at P, to increase the dynamics.
Note:
Ports X and Y are also subject to pressure when the
supply and return of control oil are “internal”.
4) Supply pressure range
The system pressure should be kept as constant as pos-
sible.
Pilot pressure range: 10 ... 210 bar or 10 ... 315 bar.
With regard to the dynamics, the dependence on the
frequency response must be taken into account within the
permitted pressure range.
5) Spool overlap
The spool overlap is stated in % of the control spool stroke.
6) Non-standard version number “100”
When not actuated (power off), channel P → B and A → T
are open 10 % of the nominal flow.
Electrically operated
2-stage servo valve,
4-way version
for external = 4WS2E
trigger electronics
Mechanical feedback = M
Nominal size 10 = 10
Unit series 50 to 59 = 5X
(50 to 59: installation and connection
dimensions unchanged)
Nominal flow 1)
5 l/min = 5
10 l/min = 10
20 l/min = 20
30 l/min = 30
45 l/min = 45
60 l/min = 60
75 l/min = 75
90 l/min = 90
Valves for external trigger electronics:
Coil No. 11 (30 mA/85 Ω per coil) 2)
= 11
100 = Special
numbers 6)
V = FKM seals 6)
suitable for mineral oil
(HL, HLP) to DIN 51524
Spool overlap 5)
C = 3 … 5 % positive
D = 0 … 0,5 % positive
E = 0 … 0,5 % negative
Electrical connection
K31 = with plug
to EN175201-804
Plug-in connector – order separately
see Page 7
Supply pressure range to 1st stage 4)
210 = 10 … 210 bar
315 = 10 … 315 bar
Control oil supply and discharge 3)
– = External supply, external return
E = Internal supply, external return
T = External supply, internal return
ET = Internals supply, internal return
(ET = Standard version)
VH1 = Valve in explosion-proof design
For details, see information on explosion protection,
Page 6
4WS2E M 10 5X B 11 VH1 K31 V 100
Included in scope of delivery:
– Valve operating instructions
– Valve fastening screws
AB
TP
a, b

T
A
P
B
T1
6
3
2
4
5
1
9
7
8
4/14 Bosch Rexroth AG Hydraulics 4WS2EM...VH1...-100 RA 29583-VH1-100-B1
Function, sectional diagram
4WS2EM...VH1...-100
Valves of this type are electrically operated, 2-stage servo
directional control valves with a mounting hole configuration
to ISO 4401-05-05-0-05. They are predominantly employed
for closed-loop position, force and speed control.
These valves consist of an electro-mechanical converter
(torque
motor) (1), a hydraulic amplifier (flapper nozzle princi-
ple) (2) and a control spool (3) in a sleeve (2nd stage), which
is connected to the torque motor via a mechanical feedback.
An electrical input signal at the coils (4) of the torque motor
causes a permanent magnet to generate a force that acts on
the armature (5) and, acting by means of a torque tube (6),
this force generates a torque. This torque then moves the
flapper plate (7) - which is connected to the torque tube (6) by
a rod - out of its central position between the two control ori-
fices (8), resulting in a pressure drop at the end faces of the
control spool. This pressure drop causes the position of the
spool to change, so that the pressure port is connected to one
consumer port and, at the same time, the other consumer
port is connected to the return port. In this special version
”100” the valve is trimmed about 10% from P → B and A → T.
The control spool is connected to the flapper plate or the
torque motor by a feedback spring (mechanical feedback) (9).
The position of the spool continues to change until the return
torque through the feedback spring and the electro-magnet-
ic torque of the torque motor reach a state of equilibrium, and
the pressure drop at the flapper nozzle system becomes zero.
In this way, the stroke of the control spool and thus the flow of
the servo valve are closed-loop-controlled proportionately to
the electrical input signal. At the same time, it should be noted
that the flow is dependent on the valve pressure drop.
External trigger electronics (order separately)
The valve is actuated by external trigger electronics (a servo
amplifier), which amplifies an analog input signal (setpoint) so
that the controlled-current output signal is capable of driving
the servo valve.
Type 4WS2EM...VH1...-100

Hydraulics Bosch Rexroth AG
RA 29583-VH1-100-B1 4WS2EM...VH1...-100 5/14
Technical data
General
Mounting hole configuration ISO 4401-05-05-0-05
Installation position Optional (ensure that pilot control is certain to receive
sufficient pressure (≥10 bar) when starting
up the system!)
Surface protection Valve body, cover and filter screw Nitrocarburized
Cap Anodized
Storage temperature range °C –20 … +70
Ambient temperature range °C –20 … +60
Weight kg 3.56
Hydraulic
Working Control oil supply pilot stage bar 10 … 210 or 10 … 315
pressure: Main valve, ports P, A, B bar up to 315
Return pressure: Port T
Internal control oil return bar Pressure peaks < 100 permitted
External control oil return bar up to 315
Port Y bar Pressure peaks < 100 permitted, static < 10
Pressure fluid Mineral oil (HL, HLP) to DIN 51524, other pressure fluids
available on request, ignition temperature > 150 °C
Pressure fluid temperature range °C –15 … +60, preferably +40 … +50
Viscosity range mm2/s 15 … 380, preferably 30 … 45
Maximum permissible degree of contamination of
pressure fluid Purity class to ISO 4406 (c) Class 18/16/13 1)
Zero flow qV,L 2) with spool overlap E
measured without dither signal l/min
pP 4) L
70bar min
• 0.7 pP 4) L
70bar min
• 0.9 pP 4) L
70bar min
• 1.2 pP 4) L
70bar min
• 1.5 pP 4) L
70bar min
• 1.7
Nominal flow qv nom 3), Tolerance ±10%
at valve pressure drop ∆p = 70 bar
(35 bar per edge)
l/min 5 10 20 30 45 60 75 90
Max. possible control spool stroke based on
mechanical end position (in case of fault) referred
to nominal stroke
% 120 … 170 120 … 150
Return system mechanically
Hysteresis (dither optimized) % ≤ 1.5
Range of inversion (dither optimized) % ≤ 0.3
Response sensitivity (dither optimized) % ≤ 0.2
Pressure gain with 1 % spool stroke
variation (starting from hydr. zero) % of pP ≥ 30 ≥ 60 ≥ 80
Zero adjustment flow
over entire working pressure range % ≤ 3, long-term ≤ 5
Zero offset on variation of:
Pressure fluid temperature
% / 20 K ≤ 1
Ambient temperature
% / 20 K ≤ 1
Working pressure 80 … 120 % of pP
% / 100 bar ≤ 2
Return pressure 0 … 10 % of pP 4) % / bar ≤ 1
1) The purity classes stated for the components must be com-
plied with in hydraulic systems. Effective filtration prevents
problems and also extends the service life of components.
For a selection of filters, see www.boschrexroth.com/filter.
2) qV,L = zero flow in l/min
3) qv nom = nominal flow in l/min
4) pP = working pressure in bar

6/14 Bosch Rexroth AG Hydraulics 4WS2EM...VH1...-100 RA 29583-VH1-100-B1
Electrical
Degree of protection of valve to EN 60529 IP 65 with correctly mounted and secured plug-in connector
Type of signal analog
Nominal current per coil mA 30
Resistance per coil Ω 85
Inductance at 60 Hz and
100 % nominal current: Connection in parallel H 0.25
In case of actuation using non-Rexroth amplifiers, we recommend a superimposed dither signal
Technical data
Type test certification FM Approved
Range of application to according
Article 505, NEC ®
IS Class I, Zone 0, AEx ia IIC T4
NI Class I, Zone 2
Ambient temperature range °C –20 … +60
Pressure fluid temperature range °C –15 … +60
Valve is only supplied with power from
certified, intrinsically safe circuits
with the following maximum values
Umax V 9.3
Imax mA 390
Pmax mW 907
Conditions for use in Zone 0 The valve cap consists of cast aluminium.
When the valve is to be used as a Category 1 device in Zone
0, the valve cap must be protected in such a manner that no
ignitable sparks from friction, impact or grinding can be pro-
duced, even in the event of rarely occurring malfunctions.
Note:
The hydraulic fluid used must have an ignition temperature of
at least 150 °C.
Required free space for burst protection The specified free space for burst protection (see Page 12)
must remain free, in order that excess pressure occurring in
the event of a fault can be dissipated through the plug in the
valve cap.
Additional requirements for use in zone 0 Safety barrier required
Additional requirements for use in zone 2 May be used without safety barrier
Information on explosion protection
Servo amplifier 1) in modular design Analog Typ VT 11021 as per Technical Data Sheet RE 29743
Recommended safety barrier 1) Single-
channel Messrs. Stahl, Type 9001/02-093-390-101
Note:
The servo amplifier and safety barrier must be operated outside the potentially explosive atmosphere!
External trigger electronics
1) Order separately

ADB
C
//
A
n.c.
n.c.
n.c.
B
C
D
E
F
PE
PA PA
ADB
C
A
n.c.
n.c.
n.c.
B
C
D
E
F
PE
Hydraulics Bosch Rexroth AG
RA 29583-VH1-100-B1 4WS2EM...VH1...-100 7/14
Zone 0 Amplifier Safety barrier Valve: Coil A Coil B
Non-hazardous Hazardous atmosphere
atmosphere
A
B
C
D
E
F
Ø8…Ø13,5
85
Plug-in connector
Plug-in connector to EN 175201-804
Metal version
Order separately under Material No. R900223890
Safety barrier required
Note
Only approved cables and leads may be used for intrinsically
safe circuits.
The Entity Concept allows interconnection of intrinsically safe
apparatus with associated apparatus not specifically exam-
ined in combination as system when:
Vmax > Voc or Vt ; Imax > Isc or It ; Ca > Ci + Ccable;
La > Li + Lcabel
Control equipment connected to barrier must not use or
generate more than 250 Vrms or Vdc.
The configuration of associated apparatus must be
FM Approved.
Electrical connection
The electrical connection may only be connected in parallel.
The electrical actuation with positive (+) to A and B and negative (–) to C and D produces a volumetric flow direction of P → A
and B → T. Inverse electrical actuation produces a volumetric flow direction of P → B and A → T.
Pins E, F and PE on the plug are not connected.
Zone 2 Amplifier Valve: Coil A Coil B
Non-hazardous Hazardous atmosphere
atmosphere
Safety barrier not neccesary

5
10
20
30
40
70
100
50
200
1
2
3
4
5
6
7
8
3020
10 70
50
40 200 300
100
1
2
8
15
45
60
75
90
60
8/14 Bosch Rexroth AG Hydraulics 4WS2EM...VH1...-100 RA 29583-VH1-100-B1
Characteristic curves (measured with HLP 32, ϑoil = 40 °C ± 5 °C)
Order
code
Nominal flow
Curve
5 5 l/min 1
10 10 l/min 2
20 20 l/min 3
30 30 l/min 4
45 45 l/min 5
60 60 l/min 6
75 75 l/min 7
90 90 l/min 8
Flow - load function (tolerance ± 10 %) with 100 % setpoint signal
Note:
Observe flow values in the max. setpoint range (see tolerance zone of flow signal function)
Tolerance zone of flow signal function
at a constant metering edge pressure drop
Flow in l/min →
100
60
80
20
40
20
60
40
100
80
–20–40–60–80
4020 60 80
110
–100
100
110
10
P → A; B → T
P → B; A → T
Flow rate in %
Setpoint in %
Typical flow
curve
Tolerance
zone
∆p = valve pressure drop
(supply pressure pP minus
load pressure pL and
minus return pressure pT)
Valve pressure drop in bar →