Marathon Monitors Inc.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Two terminal modules

 

 

 

 

 

 

 

 

 

 

 

 

Note:

Module 1 is connected to terminals 1A and 1B

 

 

 

 

Module 2 is connected to terminals 2A and 2B

 

 

 

 

Module 3 is connected to terminals 3A and 3B.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Terminal identity

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Module type

 

 

 

A

 

 

 

B

C

 

D

 

Possible functions

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Relay: 2-pin

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Unused

 

Heating, cooling, alarm,

 

(2A, 264 Vac max.)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

program event, valve raise,

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

or valve lower

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Logic - non-isolated

+

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Unused

 

Heating, cooling, mode 1,

 

(18Vdc at 20mA)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

mode 2, program event

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Triac

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Unused

 

Heating, cooling, program

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(1A, 30 to 264Vac)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

event, valve raise, or valve

 

 

Line

 

 

 

Load

 

 

 

 

 

 

 

 

 

 

 

 

 

lower

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

DC output:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Unused

 

Heating, or cooling, or

 

 

+

 

 

 

 

 

 

 

 

 

 

 

- non-isolated

 

 

 

 

 

 

 

 

 

 

 

retransmission of PV,

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(10Vdc, 20mA max.)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

setpoint, or control output

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Table 1-1 Two terminal module connections

Snubbers

The relay and triac modules have an internal 15nF/100Ω ‘snubber’ connected across their output, which is used to prolong contact life and to suppress interference when switching inductive loads, such as mechanical contactors and solenoid valves.

WARNING

When the relay contact is open, or the triac is off, the snubber circuit passes 0.6mA at 110Vac and 1.2mA at 240Vac. You must ensure that this current, passing through the snubber, will not hold on low power electrical loads. It is your responsibility as the installer to ensure that this does not happen. If the snubber circuit is not required, it can be removed from the relay module (BUT NOT THE TRIAC) by breaking the PCB track that runs crosswise, adjacent to the edge connectors of the module. This can be done by inserting the blade of a small screwdriver into one of the two slots that bound it, and twisting.

AACC 2000 Carbon

17

Nov. 1, 1997

 

 

Page 17
Image 17
Marathon Computer AACC 2000 manual Two terminal modules, Snubbers