P-K MACH
®
Gas Fired Boiler
Technical Service 1.877.728.5351
Revised: January 3, 2020
Released: January 3, 2020
Patterson-Kelley 2020
All Rights Reserved.
1004905981 P-K MACH C1500H-C4000 Installation and
Owners Manual (Rev F Jan-2020).docx
Page 74
7.1.3 Terminal Block Assignments
— High Voltage (TB2) Terminal Block
Terminal
Number
C-1500H
C-2000H
C-2500
Label
C-3000
C-4000
Label
Description
25
MASTER ALARM RELAY
Normally-Open Dry Contact, Close on Alarm
(240VAC Max Voltage & 1/2Amp Max Current)
24
MASTER ALARM RELAY
23
RELAY A
User-Configurable Normally-Open Dry Contact A
(240VAC Max Voltage & 1/2Amp Max Current)
22
RELAY A
21
RELAY B
User-Configurable Normally-Open Dry Contact B
(240VAC Max Voltage & 1/2Amp Max Current)
20
RELAY B
19
RELAY C
User-Configurable Normally-Open Dry Contact C
(240VAC Max Voltage & 1/2Amp Max Current)
18
RELAY C
17
RELAY D
User-Configurable Normally-Open Dry Contact D
(240VAC Max Voltage & 1/2Amp Max Current)
16
RELAY D
N/A
GROUND
Ground Terminals for I/O Devices
15
GROUND
14
[120V+] AIR DAMPER
120VAC Pilot-Duty for Air Damper Limit Switch
Contact Closure When Air Damper Proven Open
13
AIR DAMPER INTERLOCK
12
[120V+] AUXILIARY #1
Reserved for Future Use
11
AUXILIARY INPUT #1
10
[120V+] AUXILIARY #2
Reserved for Future Use
9
AUXILIARY INPUT #2
8
START INTERLOCK #1
External Interlock Circuit #1
7
START INTERLOCK #1
6
START INTERLOCK #2
External Interlock Circuit #2 (In Series w/ #1)
5
START INTERLOCK #2
4
GROUND G1
Unused
G1 for 110-120VAC, Single phase, 60Hz
3
NEUTRAL N1
Unused
N1 for 110-120VAC, Single phase, 60Hz
2
Unused
Unused
1
HOT L1
Unused
L1 for 110-120VAC, Single phase, 60Hz