Zener MSC-3 - HVAC Terminal Configuration (Config 3); General HVAC Setup; Essential Services Override (ESO); Local vs. Remote Control

RL1
RL2
Input reference source
8 9 10 11 12
+ -
MSC - 3 Control Board
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
Stop
Run
1k to 10k ohm
potentiometer
Single direction
2 wire control
with ESO
Local
Remote
Optional Output Disable
Essential
S
ervices Overrid
e
Power up start up
with ESO
1 2 3 4 5 6
Essential Services
Override
Optional
O
O
C
RL2 - Trip
Power On
and Stopped
C
Power On
Drive
Running
RL1 - Run
No Power
Power On
and not
tripped
Power On,
and drive
tripped
O
O
No Power
+5V D1 D2 D3 D4 EN SCN Vref IN+ IN -
COM
A B C
RS-485 / EIA-485
Serial Communications
IM00120
32
IM00120
Control connections and conguration
HVAC Terminals Typical Connection Diagram – Terminal Cong 3
General
This section shows the typical conguration applicable to pump and fan drives in the HVAC industry.
Typically these will be controlled from an external speed signal, frequently supplied from the output of
a building management system. Specic setup instructions are provided for the more common HVAC
applications in the sections that follow this.
i
Essential Services Override
(ESO)
See page 51 for detailed
information
See page 43
for details
Optional Wiring
If selection between
local and remote is
not required, place a
link between terminals
1 and 5. If the output
disable is not required
place link between
terminals 1 and 6
Local / Remote
In “local” the MSC-3
is controlled from
the front panel
console. In “remote”
the MSC-3 is
controlled from the
terminal strip.
i
The function of terminals
D1...4 are programmable. In
this conguration the following
functions are assigned to the
terminals:
I02 ~ STOP D1
I00 FWD & LATCH D2
I08 ESO D3
I11 REMOTE D4