Watlow Series SD31 PID with Optional Countdown Timer - Manual (Page 10)

Wa t l o w S e r i e s S D 3 1
■
8
■
C h a p t e r 2 I n s t a l l a n d W i r e
Figure 8a — 0 to 20 mA Process Input
(all model numbers)
• Input impedance 100
Ω
, dc only
• Controller does not supply power for the current loop
Figure 8b — Output 1 Mechanical Relay
SD31 - _ J _ _ - _ _ _ _
• Form A contact
• 2 A, resistive
• 125 VA pilot duty, 120/240V Å (ac), inductive
• See Quencharc note
• 240V Å (ac) maximum
• 30V Î (dc) maximum
• For use with ac or dc
• Minimum load current 10 mA
• Output does not supply power
Figure 8c — Output 1 Solid-state Relay
SD31 - _ K _ _ - _ _ _ _
• Form A contact
• 0.5 A maximum, resistive
• 20 VA pilot duty, 120/240V Å (ac), inductive
• See Quencharc note
• 24 to 240V Å (ac)
• Minimum load current 10 mA
• Maximum leakage current 100 µA
• Not for use with direct current (dc)
• Output does not supply power
Internal Circuitry
COM.
N.O.
Solid-state Relay
5
6
Solid-state Switch
4
56
normally open 6
common 5
Internal Circuitry
COM.
N.O.
Mechanical Relay
5
6
4
56
normally open 6
common 5
8
9
10
11
5
6
7
+
+
-
-
Transmitter
Power
Supply
Two Wire Transmitter Wiring
8
11
+
-
4
8
9
10
11
5
6
7
8
11
6
8
9
10
11
8
11
+
-
ç
WARNING: Process input may
not have sensor break protec-
tion. Outputs can remain full on.
ç
Warning:
Use National Electric (NEC) or
other country-specific standard
wiring and safety practices when
wiring and connecting this con-
troller to a power source and to
electrical sensors or peripheral
devices. Failure to do so may re-
sult in damage to equipment and
property, and/or injury or loss of
life.
Quencharc Note:
Switching pilot duty inductive
loads (relay coils, solenoids,
etc.) with the mechanical relay
or solid-state relay output op-
tions requires use of an R.C.
suppressor.
Watlow carries the R.C. sup-
pressor Quencharc brand name,
which is a trademark of ITW
Paktron. Watlow Part No. 0804-
0147-0000.
Spring clamp wiring connector
note:
To insert the wire, push the wire
into the desired connection num-
ber, and it should automatically
lock into place. To remove the
wire, press and hold the orange
release tab with a small screw-
driver. Pull the wire out of the
connection. Solid or tinned wire
recommended.