8.- WIRING

8.1.- POWER SUPPLY, RECOMMENDED WIRING

Main switch

FUSE and spare fuse.

8.2.- PROTECTION FUSES

The unit has a protection fuse located on the power supply socket. If this fuse must be replaced or changed because the power supply is changed, use the time-lag fuse according to IEC 127/2 with the values indicated on the table.

POWER SUPPLY

115 Vac (230 Vac Optional).

Power

Fuse

Supply

value

 

 

230 Vac

0.2 A

115 Vac

0.4 A

 

 

TABLE 4

8.3.- CONTROL LINES, ALARM AND SERIAL OUTPUT

 

 

Control lines connector

 

Alarm connector

Serial RS422 connector

9

1

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

A

1

6

 

 

 

 

 

 

 

 

 

 

B

 

 

 

 

 

 

C

5

9

15

8

 

 

 

 

 

 

 

 

 

 

 

D

 

 

 

 

 

 

1.-

Serial A.

1.-

Vexc.

 

 

 

9.-

Vexc.

 

2.-

Serial B.

2.-

Vexc.

 

3.-

No connection

3.-

Start

10.-

Stop

A : + Alarm

4.-

No connection

4.-

GND

11.-

Reset

5.-

GND

5.-

GND

12.-

GND

B : No connection

6.-

No connection

6.-

Minutes

13.-

Seconds

C : No connection

7.-

No connection

7.-

GND

14.-

Hours

D : - Alarm

8.-

No connection

8.-

No connection

15.-

GND

 

9.-

No connection.

8.4.- NOTES

The HOURS, MINUTES & SECONDS inputs are for contact closure to GND, and are pulled up to the auxiliary 15 volt rail through 4.7 KΩ .

The STOP, START and RESET inputs are normally configured to be pulled up to the auxiliary 15 volt rail through 1 KΩ, but may be internally jumpered to be pulled to GND through 1 KΩ , or pulled to GND through a high resistance of 100 kΩ .

Debouncing for 200 mS time constant is normally incorporated on the three control inputs, but may be disabled by removing internal jumpers.

Vexc is the Excitation Voltage for sensors supplied by the instrument (pins 1, 2 & 9). The connections to Serial A, Serial B and GND are for the RS422 data output.

Run time uncertainty

The control inputs are sensed eight times per second, but the actual run time clock is incremented or decremented in synchronism with the built in real time clock once per second.

This means that each start/stop condition may be inaccurate by up to one second.

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Omega LDP-124, LDP-126 manual Power SUPPLY, Recommended Wiring, Protection Fuses, Control LINES, Alarm and Serial Output