Euchner CES-AR-C01-AH-SA (Unicode) User Manual download pdf (Page 12)

Operating Instructions Safety Switch CES-AR-C01-AH-SA

Determining cable lengths using the example table

Example: 6 switches are to be used in series. Cabling with a length of 40 m is

routed from a safety relay in the control cabinet to the last switch (#6). Cables with a

length of 20 m each are connected between the individual CES-AR safety switches.

Figure 1: Circuit example with six CES-AR

A safety relay is connected downstream which consumes 75 mA at each of the

two safety inputs. This operates over the whole temperature range with a voltage

of 19.2 V (corresponds to 24 V -20%).

All the relevant values can now be determined using the example table:

1. Select the corresponding section in the column n (max. number of switches).

Here: 6 switches.

2. In column I

out

(possible output current per channel OA/OB), ﬁnd a current

greater than or equal to 75 mA. Here: 100 mA.

¨ It is then possible to determine the maximum cable length from the last switch

(#6) to the control system from column l

. Here: a length of 50 m is permitted.

Result: The desired cable length l

of 40 m is below the permitted value from the

table. The overall length of the switch chain l

max

of 140 m is less than the maximum

value of 200 m.

¨ The planned application is therefore functional in this form.

CES-AR # 6

Sicherheits-

relais

Safety Relay

CES-AR # 5 CES-AR # 4 CES-AR # 3

CES-AR # 2 CES-AR # 1

= 40 m

= 5 x 20 m

max

= 140 m

= 20 m

= min. 19,2 V

out

= min. 75 mA

1 2 ... 7 8 9 10 11 12 13 14 15 16 17 ... 37 38

No comments

Euchner CES-AR-C01-AH-SA (Unicode) User Manual Page 12