Technical Instructions
RL 243 MP Multi-Purpose Relay
Document Number 155-042P25
September 10, 2018
Page 6
Siemens Industry, Inc.
Direct Acting (DA) Limit
Control
Variable pressure signal from primary controller will pass directly to relay output as long
as an equal or higher pressure is available from the limit control. Spring S-1 can be
adjusted to allow a minimum output which will not be under control of the limiting device
(Figure 7).
Figure 7. Direct Acting (DA) Limit Control.
Reverse Acting (RA)
Limit Control
Variable pressure signal from primary controller will pass directly to relay output.
Maximum relay output can be adjusted with spring S-1. An air pressure signal from the
limiting device will reduce the possible output pressure an equal amount below the
maximum setting (Figure 8).
Figure 8. Reverse Acting (RA) Limit Control.
