Carbolite VST Series User Manual
Page 13
HST, VST
MF13 – 3.40
13
7.4 3-phase without neutral (delta)
7.5 3-phase without neutral (star – e.g. 380 to 415V)
7.6 Higher Voltages (e.g. 254V; 440V, 480V 3-phase)
The diagram above (7.5) normally applies, with neutral (if present) not being used.
For single phase models of 254V or above, diagram 7.1 applies except that a control circuit
transformer is included as in diagram 7.5.
e
l
e
m
e
n
t
(s)
e
l
e
m
e
n
t
(s)
Instrument Switch
coil
temperature
controller
overtemp.
controller
thermocouple
safety
switches
SSR
heat
on
F3
F1
F2
F3
L2
L3
L1
PE
SSR
SSR
F3
heat
on
F3
e
l
e
m
e
n
t
(s)
heat
on
F3
F3
if fitted
thermocouple
contactor
Filter (if fitted)
e
l
e
m
e
n
t
(s)
e
l
e
m
e
n
t
(s)
F1
L2
L3
F2
L1
PE
e
l
e
m
e
n
t
(s)
transformer
coil
temperature
controller
thermocouple
overtemp.
controller
thermocouple
safety
switches
SSR
heat
on
F3
SSR
SSR
heat
on
F3
heat
on
F3
Filter (if fitted)
if fitted
contactor
47k
47k
47k
F2
Note: in this configuration the fuses F2 on the supply side of the transformer may be
GEC Safeclip, not 32 x 6mm glass as stated in section 8.1.
Instrument Switch