8
Valve Control Module
User’s Manual
Power Supply
Power supply voltage must be within the range of the DeviceNet standard, which states:
24 volts ±1 % or adjustable to 0.2 %. Use of a lower voltage network power supply will decrease the reliability of
the network and may make it inoperable. Swagelok validated the performance of the VCM operating at 11, 24,
and 28 V (dc).
Note: Due to cable lengths and other devices operating on a network, the supply voltage at the device may not
be the same as at the power supply.
Hazardous Location Power Supply
It is required that a Class 2 power supply be used when the VCM is used in Class 1 Division 2 hazardous
locations. Class 2 power supplies have a maximum power outlet of 100 W.
DeviceNet Network Cable
Cable Length
DeviceNet network cable lengths are defined in ODVA’s
DeviceNet
Planning and Installation Manual
, chapter 1,
www odva org
. Using cable lengths longer than those recommended can result in degradation of signal
integrity and decrease of supply voltage.
Hazardous Location Cable Length
To use the cable in a hazardous location, the total inductance and capacitance of the network must be below
the values set by the power supply being used. The total value can be determined by adding together the
inductance and capacitance values of the devices on the network along with that of the cable.
The Swagelok VCM adds 0 µH and 0 µF to the network.
Cable parameters can be determined from the manufacturer’s datasheet. Assume values of 60 pF/ft and
0.2 µH/ft when that information is not available.
Cable Bend Radius
The DeviceNet network cable should not be bent too tightly, as this causes excess strain on the cable and the
attachment point on the device. After the cable has been installed, the bend radius can be adjusted as long as
it is not smaller than its fixed radius. Typical cables and their bend radii are presented in the table below. These
values may change based on the manufacturer’s recommendations.
Cable Bend Radii
Cable Type
Nominal Cable Dia
Installation Bend Radius
Fixed Bend Radius
Thick Cable
0.41 in.
(10.4 mm)
8.20 in.
(210 mm)
2.87 in.
(73.0 mm)
Thin Cable
0.24 in.
(6.1 mm)
4.80 in.
(122 mm)
1.70 in.
(43.0 mm)
Connecting the Cable
Connect the micro M12 connector end of the network cable to the network interface plug on the VCM. Connect
the opposite end to the system network.
Tubing Connections
1
2
3
4
5
V-
V+
CAN_L
CAN_H
Mechanical key
Drain
V+ = 24 V (dc) supply
V
–
= Ground
CAN_H = High signal of CAN differential
signal
CAN_L = Low signal of the CAN differential
signal
Drain = Cable shield, ground at the power
supply end
Fig. 5 M12 Female Connector End