No. 50491. 



Direct Current Experimental Switchboards with 1 Circuit and with 2 Circuits. 



119 







2 







N 



50487. 1:15. 



o 

 < 



50 490. 1 : 12 



o 



M 

 x 



any current -density (potential divider), (3) as a shunt resistance for small current-densities. For further s. d. 

 details, see under the List Numbers given. 



50.488. Travelling Type Wood Stand on which to set the switchboard so that it may be used in different rooms 2. 2. 



50.489. The preceding Switchboard (50,487) on marble slab, for fixing permanently 



to the wall . ....... 29. 0. 



Direct Current Experimental Switchboard with two Circuits for Equal Currents, 



and with Standard Type Instruments. 



5(i.4J.o. Experimental Switchboard with 2 Circuits, Wall Pattern, Type Di, Figure, for 

 connecting up to 110 160 volts Direct Current, and for taking currents of 0.03 30 

 amps, and pressures of 0.3 110 (or 160) volts in each of the two circuits, with Standard 

 Instruments and Double Switch Contact Eheostat having 30 stages 41. 0. 



The switchboard contains in each of the two circuits: -2 fuses: 1 main switch: 1 dead-beat stan- 

 dard ammeter: 1 ammeter switch: 1 switch for the shunt for obtaining potential-division; 1 36-ohm 

 regulating resistance variable in 30 steps, for a max. load of 5 30 amps.; 1 Double Switch Lever with 

 30 contacts; 1 plug box with plug and 4 m flexible; 2 terminals for connecting the switchboard to 

 the network. The board also contains for the two circuits in common: 1 dead-beat precision voltmeter 

 and 1 voltmeter switch for 4 circuits. 



Fitting a Lamp Bracket for lighting purposes, with switch and 2 fuses . . .' Extra 1. 0. 



Sliding Rheostat for fine regulation, fitted to the board, adaptable for up to 20 amps., having a resistance 



of about 0.9 ohm . '. Extra for the 2 circuits 2. 10. 



Measuring Instruments with 2 ranges, from 30 and o 3 amps, respectively and 120 and 12 volts. 



or 160 and 16 volts " Extra 3. 15. 



50,491. Travelling Type Experimental Switchboard with 2 Circuits (Type Di), cf. F i g. 50,472, 



resting on massive castors; apparatus and instruments exactly as in Xo. 50,490 . . 43.10.0 



Cl 4677, 4669. 



