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CE M11- FB P. X X X E A RTH LE A K AG E MON ITOR
M A N UA L
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Overview
Nearly all motors in industrial applications are protected against overload using TOLs, EOLs or intelligent motor control
units such as the UMC100.3. Additional surveillance with PTCs improves the protection against over temperature. Earth
faults are another important reason for motor destructions (when above named protection measures are used).
The CEM11 device monitors if the sum of the currents flowing through it is zero (factorial addition). If the sum is zero no
residual current is present. If the residual current is above an adjusted threshold value the output signal of the CEM11
changes. It can be used in motor feeders to detect leakage currents respectively ground faults caused for example by
insulation breakdowns. Detection of such ground faults can be used to interrupt the motor to prevent further damage or to
alert the maintenance personnel to perform maintenance.
Instead of “earth fault current” monitor the term “residual current” monitor is often used as well.
Product features
With only four products a wide residual current range can be covered:
Type
Pass through-hole size
Current range
CEM11-FBP.20
20 mm
80 mA … 1700 mA
CEM11-FBP.35
35 mm
100 mA … 3400 mA
CEM11-FBP.60
60 mm
120 mA … 6800 mA
CEM11-FBP.120
120 mm
240 mA ... 13600 mA
• Simple residual current adjustment with a rotary switch including test position.
• The output operates similar to a contact and can control an input that meets the IEC 61131-2 requirements for 24 V signals.
The fault free status is “closed” and has max. 4 V voltage loss (closed circuit). If a high residual current appears the output
“opens”.
• Preferably the CEM11 is used together with the UMC100.3 but it can also be used with PLCs.
• Only a two wire connection between UMC100.3 or PLC and the CEM11 is required.
• Flexible mounting options on a DIN rail (along side or cross side) or with screws/clips.
