Omega Speaker Systems CY670 Series Manual De Usuario

 

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General Comments 
Before installing the CY7/670 series sensor, 
identify which lead is the anode and which lead is 
the cathode by referring to the accompanying 
device drawings. Be sure that lead identification 
remains clear even after installation of the sensor, 
and record the serial number and location. 

The procedure used to solder the connecting 
leads is not very critical and there is very little 
danger in overheating the sensor. If for some 
reason the leads need to be cut short, they should 
be heat sunk with a copper clip or needle-nose 
pliers before soldering. Standard rosin-core 
electronic solder (m.p. 180C) is suitable for most 
applications. Applications involving the use of the 
SD package up to 200 °C require a higher melting 
point solder. A 90% Pb 10% Sn solder has been 
used quite successfully with a rosin flux. 

For all adapters except the CY, CU, and DI, the 
leads are gold-plated Kovar. Prolonged soldering 
times may cause the solder to creep up the gold-
plated leads as the solder and the gold alloy. This 
is not detrimental to the device performance. 

When installing the sensor: 

•  Make sure there are no shorts or leakage 

resistance between the leads or between the 
leads and ground. CYAV varnish or epoxy may 
soften varnish-type insulations so that high 
resistance shunts appear between wires if 
sufficient time for curing is not allowed. Teflon 
spaghetti tubing is useful for sliding over bare 
leads when the possibility of shorting exists. 

•  Avoid putting stress on the device leads and 

allow for the contractions that occur during 
cooling that could fracture a solder joint or lead if 
installed under tension at room temperature. 

The CY7/670 series sensor is designed for easy 
removal for recalibration checks or replacement, 
and the following discussions for each of the 
adapters are geared in this direction. If semi-
permanent mountings are desired, the use of OB-
CY10 or OB-CY20 low temperature epoxy can 
replace the use of CYAG grease. In all cases, the 
mounting of the sensor should be periodically 
inspected to verify that good thermal contact to the 
mounting surface is maintained. 

The SD version is the basic package for the 
CY7/670 series sensor line, from which all other 
configurations are made using the appropriate 
adapter. The base of the device has a gold 
metallized surface and is the largest flat surface 
on the sensor. The base is electrically isolated 
from the sensing element and leads, and all 
thermal contact to the sensor must be made 
through the base. 

A thin braze joint around the sides of the SD 
package is electrically connected to the sensing 
element. Contact to the sides with any electrically 
conductive material must be avoided. When 
viewed base down and with leads towards the 
observer, the positive lead (anode) is on the right. 

For a removable mount, the SD sensor can be 
held against the mounting surface with the CO 
adapter (see below) or similar clamping 
mechanism. Any method of clamping the sensor 
must avoid excessive pressure and should be 
designed so that thermal contractions or 
expansions do not loosen contact with the sensor. 
For uses restricted to below 325 K, a thin layer of 
CYAG grease should be used between the sensor 
and sample to enhance thermal contact. 

The SD package can also be bonded with a low 
temperature epoxy. The sensor should be pressed 
firmly against the surface during curing to assure a 
thin epoxy layer and a good thermal contact. The 
device may be removed in the future by using the 
appropriate epoxy stripper. 

The SD adapter can be soldered using a rosin flux 
(non-corrosive) if extreme care is exercised. 

1.  Tin the base of the sensor using a low 

wattage, temperature controlled soldering iron 
that will not exceed 200 °C. Use only a 
minimal amount of solder. Tin the surface to 
which the sensor is to be bonded and again, 
avoid an excessive thickness of solder. Clean 
both the sensor and the mounting surface of 
any residual flux. 

2.  Reheat the mounting surface to the melting 

point of the solder, press the device into 
position and allow the sensor to warm to the 
melting point of the solder. 

3.  After both tinned surfaces have flowed 

together, remove the heat source and let the 
sample and sensor cool. 

Under no circumstance should the sensor be 
heated above 200 °C and the solder must be 
limited to only the base of the sensor. Excess 
solder running up the sides of the SD package can 
create shorts. Repeated mounting and 
demounting of a soldered sensor may eventually 
cause wetting deterioration and ruin the thermal 
contact to the sensing element, although the nickel 
buffer layer should minimize these problems.