Nil. lil 573. 



Demonstration Instruments. 



905 



61 573. 



61 574. 



61 575. 



61.563. Demonstration Hot Wire Ammeter after Grimsehl (Ztschr. f. d. phys. u. chem. U. 16, s - u - 

 1903, p. 282 ; Grimsehl, p. 764), Figure; can be used for Direct and Alternating Current; 



with shunts , 1. 8. 



The instrument possesses a degree scale and a calibrating scale for the permissible currents up to 

 1 ampere. By using the shunts the range can be increased to 10 times that of the calibrated scale. 

 The pointer can be bent back so as to use either one or other of the scales. 



61.564. Dead Beat Demonstration Hot Wire Ammeter, of. P i g. 61,565, for Direct and Alter- 

 nating Current of from 5 amperes, in glass case 5. 5. () 



61.565. - - idem, with 2 ranges, F i g u r e, for 5 and 25 amperes 6. 15. 



61.566. - - idem, with 3 ranges, for 5, 25 and 50 amperes 7. 10. 



61.567. Dead Beat Demonstration Hot Wire Voltmeter for Direct and Alternating Current, 



of. Fig. 61,565, for 15 volts, with fuses, in glass case 5. 15. 



61.568. -- idem, with 2 ranges, for 30 and 150 volts 6. 15. 



61.569. -- idem, with 3 ranges, for 30, 60 and 150 volts 7.10.0 



(i 1,570. Electrostatic Demonstration Voltmeter for Direct and Alternating Current, F i g u re, 



for 1000 volts, with damping magnet 9. 0. 



61,571. - idem, for 0500 volts 9. 0. 



(i 1,572. Demonstration Wattmeter for Direct and Alternating Current, F i g u r e, for 10 amps. 



and 125 volts, with damping 8. 0. 



If desired, and at a proportionate variation in price, the wattmeters can be supplied for other current 

 maxima between and 50 amps, and for other voltages. 



61, 573. Demonstration Ammeter, Hummel-Schuckert system, Figure, from 1.3 amps., 



for projection 3. 15. 



til, 571. Demonstration Ammeter, Dobrovolski system, Figure, from to 10 amps., for 



projection 3. 15. 



61,575. Demonstration Galvanometer, Deprez-d'Arsonval system, Figure, graduated from 



30 milliarnperes, for projection 5. 10. 



This instrument can also be supplied graduated as a volt- or ammeter. 



Technical Measuring Instruments. 



Precision instruments constructed on the Depree-d'Ajsonval system can be recommended 



before all others for Direct Current, as they are most accurate, dead-beat and possess an even gra- 

 duation commencing from zero. The electromagnetic instruments for direct or alternating current 

 have an air damping arrangement which is efficient in its action. Their finer graduation commences 

 at about ' ' 5 of the maximum deflection. When ordering it should be precisely stated whether these 

 instruments are intended for Direct or Alternating Current. In addition, the periodicity should be 

 given, otherwise instruments for 50 cycles are supplied. 



For accurate measurements on Alternating Current it is advisable to use Hot Wire Instruments 

 and Dynamometrical Instruments. In these instruments also the finer graduation commences at 

 about V 5 of the total deflection. The round pattern instruments are, unless otherwise stated, sup- 

 plied for front connection. 



