Festo Пропорциональные регуляторы давления MPPE - Handbuch (Seite 7)

Type Setpoint signal range Pressure range
MPPE-...- (P u )-P o -010B DC 0 ... 10 V P u ... P o bar
MPPE-...- (P u )-P o -420B 4 ... 20 mA P u ... P o bar
e.g. standard version
MPPE-3-1/4-2,5-010B DC 0 ... 10 V 0 ... 2.5 bar
e.g. special adaptation
MPPE-3-1/2-1,5-7-420B 4 ... 20 mA 1.5 ... 7 bar
Fig. 14
For shorter air supply times:
• Check the permissibility of an external pressure sensor according to the criteria
in Fig. 15:
The pressure sensor must exhibit the same pressure range and the same signal
variant as the MPPE-... (current and voltage variant).
Tube length
. 5 m , 5 m
Cylinder volume . 5 l
, 5 l
Fig. 15 Permissible use of a pressure sensor
• Use the external pressure sensor directly on
the cylinder.
Because differences in pressure can occur
between the valve and cylinder which the in-
ternal pressure sensor of the valve does not
detect.
Fig. 16
P
I
P in 1
> 5 m
> 5 l
• Wire the actual output value of the external pressure sensor to Pin 1 on the
MPPE-... (input X). The external pressure sensor is then queried automatically
instead of the internal pressure sensor.
For visual inspection of the control process:
• Wire the MPPE-... with the following measuring device according to Fig. 17:
Voltage variant (voltage measurement
device) Current variant (Am-meter)
6
8
V
6
8
A
Fig. 17
The actual electrical value can be tracked on the display of the measuring device.
This changes proportional to the pressure curve at air supply port
2.
6 Operation
Hinweis
• When switching off the power supply make sure that the compressed air is
switched off as well. Otherwise pressure can build up at the valve outlet.
• Make sure the supply pressure P
E
, the output pressure P
A
and the proportional
actual value w always exhibit the following relationship:
0 bar
< P
A
( ≅ w) < P
E
If not, the MPPE-... will wear prematurely through continuous/normal operation.
• Listen for operating noises from the valve ( Fig. 18).
Noise Significance
Slight babble: Normal control procedure
Heavy babble: Wear!
Fig. 18
If the same output pressure is still evident despite a modified setpoint value
specification:
• Look for defective cables.
In the event of fractured setpoint cables (MPPE-...-420B only) or power supply
cables, the last specified output pressure is maintained but
not regulated. Leak-
age produces a change in output pressure over the long term. The pressure may
rise or fall.
7 Maintenance and care
• Clean the MPPE-... with soap suds only (max. +60 °C).
8 Accessories
www.festo.com/catalogue
9 Troubleshooting
Malfunc-
tion Possible cause Remedy
MPPE-… does
not respond Supply voltage not present Check the 24 V DC supply
voltage connection
No set value voltage Check control unit; check
connection
Supply pressure P E not present Increase the supply pressure
above the desired setpoint
pressure. The supply pres-
sure must be lower than the
maximum permissible value
(
Technical data).
MPPE-… defective Return the MPPE-... to Festo
Flow too low Restriction of the flow cross section due to
connection technology (swivel fittings, silencer
too small) Use an alternative connection
Pressure in-
crease too
slow Large cylinder volume ( > 5 l) and tube length
( > 5 m)
Connect the external pres-
sure sensor to the cylinder
(
Commissioning)
Heavy
babble
produced by
the MPPE-... Supply pressure P E not present/setpoint signal
V ref not present (corresponds to the setpoint
pressure P A)
Increase the supply pressure
P
E .
(P A < P E < P max. Technical
data)
Only applicable for MPPE-...010B (voltage
variant) with hardware version from 1.11.98 (see
rating plate) without external pressure sensor:
Pin 1 (Xext_in) is not connected to GND Connect Pin 1 (Xext_in) to
GND
Fig. 19
10 Technical data
10.1 General data
Voltage variant:
MPPE-3-...-010B ≅ DC 0 ... 10 V)
Current variant: MPPE-3-...-420B ≅ 4 ... 20 mA)
Type MPPE-…
Design Proportional pressure regulator
Mounting position As desired, preferably vertical (electronics upward)
Medium Compressed air to ISO 8573-1:2010 [7:4:4], inert gases
Working pressure Constant (independent of fluctuations in the compressed air supply).
Supply pressure at least 1 bar higher than the max. output pressure
Normal leakage in
new condition < 5 l/h max
Protection class IP65 in combination with plug socket according to accessories
Permitted
temperature range Ambient temperature: 0 ... + 50 °C
Storage temperature: - 20 ... + 70 °C
Medium temperature: 0 ... + 60 °C
Permitted supply
voltage DC + 18 ... max. 30 V (nominal value: DC + 24 V)
Reference output
current at DC 10 V < 5 mA
External setpoint
value potentiometer 2 kΩ ... 10 kΩ, recommended 4.7 kΩ
Power consumption max. 3.6 W (at U vmax = DC 30 V )
Electromagnetic
compatibility
1)
See declaration of conformity
www.festo.com
Linearity 1 % Full Scale
Electrical connec-
tion Pin contact, 8-pin according to DIN 45326
Resolution of actual
value output 8 Bit (approx. 40 mV for voltage variant/approx. 0.0625 mA for current
variant)
Safety setting If the power supply cable or the setpoint cable (current) breaks
(MPPE-...-420B only), the output pressure is maintained unregulated. In
the long-term, a leak will cause a reduction in pressure.
In case of a setpoint cable break (voltage) the output pressure is set to 0
bar.
Materials Housing: Aluminium
Cover: Die-cast zinc
Seals: Nitrile rubber
Sealing compound: Polyurethane
Lubrication:
Silicone-free
Setpoint variable:
Permissible load
resistance:
Input resistance: 0 ... +10 V (voltage variant) 4 ... 20 mA (current variant)
min. 2 kΩ (voltage variant) max. 500 Ω (current variant)
10 kΩ (voltage variant) 250 Ω (current variant)
1) The valve is intended for use in an industrial environment. Outside of industrial environ-
ments, e.g. in commercial and mixed-residential areas, actions to suppress interference may
have to be taken.
Fig. 20