User manual ROTOTHERM SERIES 33 RECORDER

[. . . ] Three pen: red, blue and green Glass filled polyester resin. 200 to 250 volts, 50 Hz (60Hz available); 100 to 110 volts, 50 Hz (60Hz available). Instruments without electrical control require no power supply provided that a clockwork drive is fitted. Battery operated chart drives require 1. 5 volt 'C' type cell. INTRODUCTION The RTO and RPO series of instruments are designed to measure, record and control process variables such as temperature, pressure and humidity. [. . . ] For high alarm set point, slacken the lock nut, securing the high contact adjustment screw and screw the adjustment until the moving contact just makes contact with the low contact at the point required, the set point. Note: For the low alarm, unscrewing the adjustment reduces the set point and for the high alarm, unscrewing the adjustment increases the set point INKING SYSTEM The writing system uses the fibre pen capsules. A recess on the capsule fits onto the pen arm and the pen capsules are easily replaced when the ink is exhausted. To fit a capsule, pull the arm gently clear of its mountings, slide off the used capsule and replace it with a new one of the appropriate colour. Where there are two or more measuring systems, different colour inks are used to distinguish the traces. The fibre tip is protected by a plastic cap, which should be removed by pulling in line with its length, gripping the end only and gently twisting. The upper pen (red) has a long fibre Tip compared to the lower pen (blue) which has a short fibre tip. On instruments fitted with a third measuring system, the third pen (green) has the longest fibre tip. All recorders and recorder controllers are fitted with disposable fibre tipped pens. The recorder pen arm is removable from the pen mechanism see fig. It is advisable to remove the pen arm from the mechanism of recorders when fitting new pens because of the possibility of undue forces being applied to the mechanism thus causing a possible error shift. Transfer the bulb to the high temperature bath, allow sufficient time for the bulb to attain the bath temperature and note the position of the pen. If the pen rests below the correct line, halve the error by adjusting the ranging screw (5 or 6) anticlockwise. If the pen rests above the line, adjust the ranging screw (6) clockwise to bring the pen to the top of the chart. Return the bulb to the low temperature bath and adjust the zero nut (4 or 14) to bring the pen to the correct line. Check the top point and if still in error, repeat steps 4 and 5 until the bottom points are correct. If the pen reads correctly, the instrument can be put into service. If there is an error note its magnitude and proceed to step 8. Ease the pen arm boss (12) from the spindle taper and set the pen approximately 8 times the value of of the error on the opposite side of the mid-chart line. This adjustment is not possible on instruments fitted with differential contact mechanisms as the pen boss is factory set. Return the bulb to the low temperature bath and adjust the zero nut (4 or 14) to bring the pen to the correct value on the scale. If not correct, repeat step 8 (the multiple of 8 is a value, which in most cases, will correct the midpoint error). [. . . ] Open the recorder door and remove the pen(s) and chart plate. If the lower system of a duplex instrument is faulty, unscrew the zero nut (12) and remove compensation washers (11) from the link (8), noting the number and arrangement. (these items will be required for the new systems). Remove the two Bourdon securing screws (9) and slide the Bourdon, including overload spring assembly (10) off the screwed link (8). [. . . ]