75 0 NATIONAL COURT, RICHMOND, C

COLOR ALARM Co. Derip) SPECIFICATIONS Operation on I I5 or 230 volts 50 60 cycle AC. Tube comple. ment consisting of two photo. tubes, one power pentode, one thyratron. Flow cell is designed for operation on pressures "(z to 50 psi tested at 150 psi Provided with l/s" NPT i&i and outlet openings. Instrumeni requires flow of approximately 50 cc per minute. Model 1015- Explosion Proof Aluminum &Se Approximate Weight-25 Ibr. Dimensions - 7"~ I 2 % "x 7h "

The Color Alarm is a differential type calorimeter providing an alarm or a visual signal when a prerer color limit IS exceeded. It is a compact, simple and inexpensive continuous flow color indicator utilizing phototubes and an ampli fier which actuates the signal device. THEORY OF OPERATION A low-powered radio panel lamp provider a source of light. A part of this r * c light traverser the sample cell ish own in upper left-hand corner of lower photograph1 and is then reflected by a mirror so that it again traverser the cell in the opposite direction, falling on a phototube. A second photo- tube, used as a reference, receives light from the same source. This refer- . c ence photatube is covered by a cylindrical rotating shield having a wedge- shaped opening. The shield can be rotated externally by a knob that is fastened to a shaft which passer through the cover. A painter on the knob and a scale on the cover permit adjustment of the wedge so that a proper l b amount of light is focused on the reference phototube. thus balancing the circuit for the color of the material present in the cell. A darker liquid flowing through the cell will unbalance the circuit, causing a relay to op- erate which de-energizes one signal light and energizes the other. One . . light indicates that the sample flowing through the cell is as light or lighter in color than the sample to which the instrument was adjusted. The other 3 light indicates that it is darker. A spare set of relay contacts is provided in the instrument so that an external audible signaling device (not included . with the instrument1 may be used. O/h,- ,,~odel, ,,rr ,,r~,/iloble for <<,,,I; ,,,,,,,, r/p ;,,d;r,,t;,,g, rrr,,rd;,,g .,vd ro,,,roll;,,g. cu. I>

ANALYTICAL INSTRUMENTS FOR CONTINUOUS PROCESSES