Siemens ISI EN 50295 Brochure page 52

AS-Interface Slaves
I/O modules for operation in the field
Digital I/O modules IP68 / IP69K - K60R
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Design (continued)
Connection
6
In the IP67 environment, the proven standard components are
connected using ribbon cables. Branch lines are made into
the IP68 environment via a round cable distributor (3RK1901-
1NR00). The module is connected using a round cable with M12
socket. The module has an M12 bus connection for this instead
of the previous addressing socket. The AS-Interface bus cable
and the 24 V DC power supply are routed together in a 4-con-
ductor round cable. This round cable must not have an earthing
conductor. The earthing connection is made via the mounting
plate.
Only cables with molded M12 plugs may be used in the IP68 en-
vironment. This cable is available as a preassembled M12 cable
plug/socket:
• 3RX1641: 0.5 m long
• 3RX1640: 1.0 m long
• 3RX1642: 1.5 m long
Freely-assembled cables with an M12 cable socket and a free
cable end can be used for the connection between the distribu-
tor and K60R module over longer distances, where the free end
is fitted with an M12 plug (straight version: 3RX1586, angled
plug 3RX1587) and connected to the distributor. This cable is
available in two versions:
• 3RX1536: 5 m long, with M12 cable socket
• 3RX1542: 5 m long, with M12 angled cable socket
If more than one K60R module is to be connected to a branch
line, this can be distributed further using a T-distributor
(3RK1901-1TR00) in degree of protection IP68.
6/52 Siemens IK PI · 2004
The following conditions must be observed:
lines for the AS-Interface are applicable. The maximum permis-
sible current is limited to 4 A for all M12 connection cables.
The cross-section of these cables is only 0.34 mm². The M12
connection cables mentioned (max. length 5 m) can be used for
the branch lines to connect the K60R modules. The voltage drop
resulting from the ohmic resistance (approx. 0.11 /m) must be
taken into account. The total maximum load for all four connec-
tions of the round cable distributor 3RK1901-1NR00 is 4 A.
In applications with only round cables, the AS-Interface bus ca-
ble and the 24 V DC power supply can be routed together up to
20 m when using a round cable 4 x 1.5 mm². With longer cables,
routing is made using two separate cables of 2 x 1.5 mm² each.
A round cable distributor (3RK1901-1NR00) is not required for
such applications. Distribution to the K60R modules is then
made using a terminal box and the M12 cables referred to.
IP68 / IP69K tests
K60R modules are tested as follows:
• Extra testing compared to IP67:
(IP67: 30 min under 1 m water)
• Salt water test: five months immersed in salt water, 20 cm deep
at room temperature
• Test with particularly creeping oil:
der oil at room temperature
• Test with drilling emulsion: five months at room temperature
(components of drilling emulsion: anionic and non-ionic emul-
sifiers, paraffinic low-aromatic mineral oil, boric acid alkanola-
mines, corrosion inhibitors, oil content 40 %)
• Test in oil bath (Oil Excellence 416) with changing oil tempera-
ture: 130 cycles from 15 to 55 °C, two months
• Cleaning with high-pressure cleaner according to IP69K:
80 to 100 bar, distance 10 to 15 cm, time per side > 30 s, water
temperature 80 °C
In order to simulate demands which are as realistic as possible,
the modules have been artificially aged prior to the tests by 15
temperature cycles of -25/+85 °C. The modules were connected
by 3RX1 cables during the tests. Unused connections were
closed by sealing caps 3RK1901-1KA00.
Note: Sealing caps and M12 connections must be tightened with
the correct torque.
The design guide-
90 min under 1.8 m water
five months completely un-