TYPE 04—Standard Electric Time AR-2A Two-Wire, Dual Voltage

Each minute, from 58 seconds to 00 seconds, a low-voltage pulse (24Vdc) is transmitted. The secondary clocks receive the pulses until the 59th minute. At this time, from 50 seconds to 00 seconds, a higher voltage pulse (48Vdc) is required to advance to the hour.

Manual clock advances and daylight saving advances cause the master clock to transmit 62 pulses (one second ON and one second OFF at 0.5Hz), all at 24Vdc. Normal minute pulses are inhibited during these pulses.

X = Normally open contact

I = Normally closed contact

2 = 1N4004 diode or equal

 

 

 

 

 

 

 

 

RELAY

 

 

RELAY

 

 

 

 

 

K5 (K7)

 

 

 

K6 (K8)

 

 

 

 

 

 

 

 

x

 

x

I

 

I

 

 

 

 

 

 

 

x

 

 

CLK1 OR CLK2

 

 

 

 

 

 

 

MASTER CLOCK

1

2

3

4

5

6

7

8

FIELD CONNECTIONS

 

 

 

 

 

 

 

 

24Vdc

 

 

 

 

 

 

 

10 ASB MAX.

 

 

 

 

 

 

 

 

48Vdc

 

 

 

 

 

 

 

AB

 

 

 

 

 

 

 

 

2

RTN

 

 

 

 

 

 

 

PC

Figure B-5

Standard Electric Time AR-2A Two-Wired, Dual Voltage

24A715/24A715M Master Clock Installation Manual

B-7