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NVS Range Users, Installation & Servicing Instructions Doc Ref M102 issue 2.4 May 2018.
2.4.2 Initial Wiring Instalation
Key
A =
2 core and earth
B =
Powrtrol =
4 core and earth
Powrtrol RR=
6 core and earth
MC200 On/Off = 6 core and earth
MC200 Hi/Lo = 7 core and earth
MC200 Mod = 8 core and earth
C=
4 core and earth
D=
Screened 2 core (MC200 models only)*
* (screen must be grounded only at the MC200, See
instructions supplied with controller for wiring sizing,
Max. 100m)
Model
F - Free Blowing
Unit
Fuse Rating (A)
'C' - Centrifugal
Unit
Fuse Rating (A)
NVS30
2
5
NVS60
3
16
NVS90
5
16
NVS140
7
25
Note:
To achieve maximum system efficiency it is
recommended that NVx units are controlled
by an MC200 Fuel Saver unit. Simple room
thermostat and thermostat/time clock control systems will
not provide optimum system efficiency and fuel savings.
Wiring drawings and instructions are supplied with the
respective controller.
2.4.3 External Wiring
The wiring terminals are located inside the electrical box
behind the side door which firstly has to be opened.
The mains supply connections are via a Hylec terminal
block. Control Circuitry connections are via a 30A
numbered terminal strip. They are:
terminal 1 - 230V Heat Demand
terminal 9 - 230V Main Fan Only
terminal 13 - Burner reset - Neutral Switch
terminal 14 - Lockout indication 230V Output
terminal 16* - 0V (modulating negative)
terminal 17* - 0 - 10V (modulating) OR 230V High
Fire
*
Used where required
2.4.4 External Fuses
NVS/D models supplied less fan must be electrically
interlocked to the air movement system so that this is
started in the same manner as the air heater fan would be
viz. A connection from heater terminal number 9 must be
made to one side of the fan motor contactor coil, the other
side of the coil being connected to Neutral. The fan motor
electrical supply must not be taken direct from the internal
wiring of the NVS heater.
L
N
E
t14
t13
t1
t9
