Installation
14
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2021 KEB America, Inc.
4.1.3 AC vs DC Switching Summary
The following table shows a summary of pros and cons of AC vs DC side switching for
ease of reference. Select the type of switching that best fits the application.
Category
AC
DC
Brake* release time
+
+
Brake* engage time
-
+
Small switching contactor
+
-
Minimal arcing across switch contact (reduced wear and tear)
+
-
Higher safety for hoists and lifts
-
+
*refers to a KEB COMBISTOP spring applied brake
4.2 Connection Diagrams
The voltage rating of the clutch or brake coil and the available supply voltage will
determine what type of rectifier is required. In general the DC output voltage from a full-
wave rectifier is 0.9 times the AC input, whereas the DC output voltage from a half-wave
rectifier is 0.45 times the AC input. The correct rectifier must be selected based on the
rated voltages of the supply and load. The following diagrams provide examples of the
most common scenarios, however not all possibilities are covered. Please consult KEB
for further assistance if the configuration needed is not found below.
AC Side – Relay Switching – Phase to Neutral
Figure 4.2.1
Switching: AC Side
Rectifier: Full-wave
Model Number: 0291020-CE07
Line Voltage: 120VAC
Input Voltage: 120VAC
Coil Voltage: 105VDC
F
brk
= Class CC fuse max. 5A Relay Contact: 120VAC 5A
