JUMO 709051, Operating Manual, Page: 71 / 92

V1.00/EN/00741192/2021-03-30 [IPC 300] 71
6 Special device functions
6.6 Current limiting
Function Current limiting is implemented via amplitude control. It prevents overcurrents
in the load circuit and limits the load current independently of the load resis-
tance and the setpoint value to the required current limit value.
Current limiting is unavoidable for heating elements with a high positive tem-
perature coefficient, such as Kanthal-Super, for example. Without current limit-
ing, the load current would accept inadmissibly high values when such heating
elements are in a cold state.
Default setting Current limiting is not active.
If necessary, current limiting must be switched on in the configuration level.
v
Chapter 5.1.2 "Power controller"
The current limit value can be adjusted both in the configuration level or in the
operating level. In the operating level, it can be adjusted during operation.
6.7 Firing pulse inhibit
The inhibit function serves to protect the IPC 300 and the connected loads.
Internal The IPC 300 is locked in the event of:
- Switch-on of voltage supply for control electronics (DC 24 V)
- Changes in the configuration level
- Internal voltage supply that is missing or too small
- Setup of data transfer to the device
- Device temperature greater than 115 °C
External The IPC 300 can also be switched off via the "Inhibit" digital input
v
Chapter 3.4 "Switch-on sequence"
or via the RS422/485 interface.
Caution!
The firing pulse inhibit does not disconnect the load.
The load connection terminals are at mains potential as the IPC 300 does not
galvanically isolate the voltage supply!