Ii controller will result – Dwyer DHII User Manual
Page 4
3
Notes:
1. The instrument may be powered from the AC line or 24 VDC. Do not wire AC line terminals 1-2 on
the lower board and 24 VDC terminals 4-5 on the upper board at the same time or damage to the
unit will result.
2. For supply connections, wire in accordance with an equivalent national standard or code. Use
copper conductors only rated for at least 75°C.
3. Terminals on upper board are rated CLASS 2.
4. ISOLATION:
Relays - 1500 VAC to all other inputs and outputs.
AC Line Power (terminals 4-5) - 1500 VAC to all other inputs and outputs.
RS485 output - 500 VAC to all other CLASS 2 wiring.
The 24 VDC Power, 4-20 mA transmitter, and Remote Reset Switch share a common
ground.
5. The Remote Reset Switch must be a dry contact switch.
6. Shielded cable is required for RS485 wiring.
WIRING
WARNING
If Digihelic
®
II Controller is powered by 24 VDC, the device receiving the 4-20 mA
transmitter output MUST NOT share a common ground with the 24 VDC supply or
damage to the Digihelic
®
II Controller will result.
ƽ
1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
1
1 2
2 3
3 4
4 5
5 6
6 7
7 8
8
CONNECTOR
CONNECTOR
ON
ON
LOWER
LOWER
BOARD
BOARD
CONNECTOR
CONNECTOR
ON
ON
UPPER
UPPER
BOARD
BOARD
100-240
100-240 VAC
VAC or
or
132-240
132-240 VDC
VDC POWER
POWER
NOTE
NOTE 1
1
3/8
3/8 A
A 250vac
250vac
MEDIUM
MEDIUM LAG
LAG
N/C
N/C
N/C
N/C
N/O
N/O
N/O
N/O
C
C
C
C
SP1
SP1
RELAY
RELAY
SP2
SP2 OR
OR
ALARM
ALARM
RELAY
RELAY
A-
A-
B+
B+
RS485
RS485 SERIAL
SERIAL
COMMUNICATION
COMMUNICATION
+
+
--
24
24 VDC
VDC POWER
POWER
NOTE
NOTE 1
1
REMOTE
REMOTE
RESET
RESET
SWITCH
SWITCH
Device
Device receiving
receiving 4-20mA
4-20mA
signal.
signal. Check
Check specifications
specifications
of
of this
this device
device for
for input
input load
load
resistance.
resistance. Typical
Typical 250
250 to
to
600
600 OHMS,
OHMS, 900
900 OHMS
OHMS
maximum.
maximum.
+
+
--
4-20mA
4-20mA
TRANSMITTER
TRANSMITTER
OUTPUT
OUTPUT