KROHNE MAC 100 EN - Manual (Page 31)

ELECTRICAL CONNECTIONS
4
31
OPTISENS MAC 100
www.krohne.com 04/2011 - MA OPTISENS MAC 100 R01 en
4.10.2 Connecting the relay outputs
AC voltage: required capacitors and resistances for dejamming
DANGER!
To avoid dangerous voltages, the switching voltage for the relay contacts must fulfill one of the
following conditions: it must either originate from the same network as the signal converter
power supply including pre-fuse and separator (see Section 4.6) or come from a SELV or PELV
network. When installing, always comply with the prevailing national and international
regulations and standards.
CAUTION!
If you want to switch inductive loads (even relays or protection coils), you always have to dejam
them! Otherwise there may occur interferences with the measuring signal. Also note the
following items:
• If you use DC voltage, dejam the relay coil with a free-wheeling diode; refer to the following
table and the following drawing "Interference suppression"!
• If dejamming is not possible, you have to assure that the relay contact is protected by a RC
protection circuit! Also refer to the following table.
• If you use potential-free relay outputs, assure that a suitable shut-off device and a pre-fuse is
installed in the feed line on site.
• When switching inductive loads, the manufacturer recommends a protective circuit to avoid
unnecessarily high contact burn on the relay contact!
INFORMATION!
In delivery condition, the relay contacts are also suitable for low signal currents (from
approx. 1 mA). Please note that the gold plating burns off during the switching operation when
larger currents are used (from approx. 100 mA). Afterwards, the relays can no longer reliably
switch small currents!
Current up to Capacitor Resistor
60 mA 10 nF / 260 V 390 Ω / 2 W
70 mA 47 nF / 260 V 22 Ω / 2 W
150 mA 100 nF / 260 V 47 Ω / 2 W
1.0 A 220 nF / 260 V 47 Ω / 2 W
.book Page 31 Friday, April 1, 2011 4:59 PM