HEIDENHAIN TNC 122 Technical Manual - Manual (Page 9)

8
TNC 122 5 Power Supply 4/97
5 Power Supply
The voltage must comply with specifications:
Component Power supply Voltage range Max. power
consumption Power consumption
NC Primary clocked
power supply 100 – 240 V
(–15% to +10%)
48 – 62 Hz — Approx. 19 W
PLC 24 V
(with basis
insulation
according to
EN 50 178) Lower limit
20.4 V
__
....
Upper limit
31 V
__
.... 1)
Max. 10 mA per input
Max. 100 mA per output
1) Voltage surges up to 36 V
__
.... for t < 100 ms are permissible.
All small contactors and relays must have a quenching diode.
PLC power supply
The PLC (PLC inputs and outputs) of the TNC 122 is powered from the 24 V machine control voltage
supply.
Danger to internal components!
Connect inductive loads only with a quenching diode parallel to the inductance.
Superposed AC components as they arise from a three-phase bridge rectifier without smoothing
(see DIN 40110/1075, Section 1.2) must not exceed 5%. This results at the upper limit in the
absolute value 33.4 V and at the lower limit the absolute value of 18.5 V.
32.6 V
31 V
20.4 V
18.5 V
U
t
To increase the noise immunity, connect the ground terminal on the rear panel to the
central ground point of the machine.
(Minimum cross-section: 6 mm
2 )
The 0 V line of the PLC power supply must be grounded with an earth lead (
∅ ≥
6 mm 2 ) to the main
frame ground of the machine.