MERLIN NX IP AND MST/TP VAV CONTROLLER - INSTALLATION INSTRUCTIONS
17
EN1Z-1076GE51 R0722
UIO Wiring Examples
Fig. 18 Universal IO Wiring Examples
NOTE:
• The UL Standards recommends that all wiring connections for the IO, DO (SSR), 24 VAC, and 20 VDC circuits
must be restricted to the same room.
• A protective diode is recommended in any circuit that allows the flow of current in the forward direction
because the current will not flow in the reverse direction. The diode protects components sensitive to a flow of
current in the wrong direction.
19
20
21
22
23
24
25
26
27
28
29
IO1
C
IO2
IO3
C
IO4
IO5
C
IO6
C
IO7
UIO1 - UIO7 Universal Input / Output (UIO)
UO1 - UO7 Output Connection Example
UI1 - UI7 Input Connection Example
Ensure
correct
polarity
+
-
0 to 10 VDC
V
Voltage Input
Thermistor / Resistive Input
Dry contacts / Digital Input
Current Input
100 to
100 k
:
e.g.
20 kNTC
PT1000
dry contact
contact
open
collector
Ensure correct
polarity
logic
circuit
DIGITAL
0 V
IO
C
+
-
VV
IO
IO
C
IO
C
IO
C
S
External
Power
Supply
Ensure
correct
polarity
SSS
S
0V IN
IN 0V
0V IN
Output Type
Load
0 to 10 VDC, 10 mA max.
1 k
:
4 to 20 mA
550
:
IO
C
IO
IO
C
Externally Powered
minimum
wetting
current
3.5 mA
IO
C
Voltage Output to Power External Relay
+
-
Ensure correct
polarity
The rating of the diode
must be 11 V and 22 mA
maximum.
IO
C
0 to 10 VDC
DC LOAD
Ensure correct
polarity
Analog Output (UIO)
+
-
IO
C
Analog Output (UIO) provides a variable
voltage between 0 to10 VDC and the
output can source up to 20 mA.
Pulse Meter (Type 1: Pulse
with Power 5-30 V)
Pulse Meter (Type 2: Pulse
without Power)
IO
C
V
+
_
IO
C
IO
C
LOAD
SUPPLY
RELAY