"Bench" testing a Westinghouse HL Control Unit Switch and Master Controller.
This system will be installed in the Portland Lewiston Interurban's Car #14 "Narcissus"

https://youtu.be/hq-1Efl9j2s

This is an excellent and easy to follow description and demonstration of HL control. Thank you for sharing this!

Best wishes,
Matt Nawn

That's an interesting video, Brian. I know #14 was acquired as a body and presumably the mechanical components came from Seashore's spare parts supplies over the years. But the "L" in "HL" stands for line-voltage control (600VDC). In the video, you indicated that you were using low voltage at the master controller to sequence the box. Typically in HL control, there is a type 189 tapped dropping resistor going between T, 5 wire, 6 wire, 7 wire, G. It creates approximately 150V between G and 7, 7 and 6, and 6 and 5. Different parts of the circuit work between different potential points to keep things balanced. The magnet valves are designed for 150VDC nominal but they will usually pick up as low as 50V and will withstand being operated at 200+ VDC. The coils will have a resistance in the 300-500 ohm range.

So I'm curious how this test was set up to excite the magnet valves. What voltage was used?

During initial testing of an HL group of uncertain status, megger tests should be made between the power leads (R1, R2, etc.) and the frame (obviously, with the power off). Each contactor should be megger tested across the contacts and from each contact to ground. If there is a failure, examine the ball insulators between the piston and the moving contact arm, and similar insulators at the top of the frame which support the stationary contacts and the bus-bar jumpers between contacts. Coils should be megger tested to ground (lift wires from the coil terminals to isolate) as well as tested for resistance. Coils which vary more than 10% may be partially shorted or "weak"

In a full bench rebuild, each contactor unit is removed, disassembled, cleaned, and tested. Magnet valve travel and gap is measured and compared to the spec (see the WH HL handbook) Sometimes, although rare, magnet valve stems become worn to the point that there is almost 0 gap between the armature and the coil core when energized. This can manifest as contactors that "stick" or drop out sluggishly.

Pneumatically, there should be no audible leakage from any magnet valve while in the OFF position. In the ON position, neither the magnet valve nor the piston should have audible leakage.

There are two potential problems with HL, PC and similar groups having to do with timiing.
Usually I do two tests on groups like HL or PC with 600V power on: Install a bank of 5 lights across the open main motor power disconnect switch. With the motors cut-in, run the sequence and observe that the lights come on and remain on through all points, with no momentary flicker whatsoever. This proves that there are no open circuits in the sequence. For example, if say two contactors are designed to have overlap (break before make) but they don't, then the light will flicker. I thought I saw that symptom in your video in the 7th notch, but it is hard to see with a video. Momentary opens are undesirable because they will cause a heavy arc at the affected contactor.

he second test is to isolate all the motors (in your case that is easy since the group is not connected) either with the MCOs or by slipping card stock under the appropriate fingers in the reverser. Now run the sequence again and verify that the lights NEVER come on. A timing problem can arise where G comes in before S has dropped out and if so, this will cause a dead short and blow the power.

In the case of HL control specifically, timing is driven primarily by the fingers and segments of the master controller. There are also interlocks on some contactors such as P, S, G.

Make sure when the HL group is installed on the car that there is an insulating pipe fitting in the compressed air line. The entire frame is designed to be "floating" the same as the grids. Also make sure the piping has a drip leg so moisture drains away from the magnet valve manifold. Put a drain valve at the bottom of the drip leg. On HL installations where this is not done and where it gets humid (for example, Maine in the summertime) the condensate buildup will eventually cause scaling and failure of the magnet valves.

The "Narcissus" has been an on-again, off-again restoration for as long as I can remember. If this car is getting close to completion, that is exciting news.

Thanks Jeff,
Your testing suggestions will be very helpful. We have a number of documents on HL but I'm not sure if we have what you refer to as the HL handbook. More detail on that would be appreciated. As you suspect these components came from Seashore's inventory. Donald Curry took me on a hike out back several years ago. He told a story of one day about 55 years ago when one of the members called our shop and said "get the dump truck down here. The Everett Shops are cleaning out their obsolete parts warehouse".

The modern day trek led us out back to an old decaying ice cooled refrigerator car full of parts. The unit switch was found deep inside. The master controllers came from inside another box car located elsewhere on campus. The reverser has seen more weather but should be salvageable.

I believe Brian did meg the master controller when it was being cleaned up. This early experiment used 110 AC as the "traction power" and a bench supply with I think about 40 volts DC for the "low voltage." We knew that the low voltage should have been higher and were a bit surprised the valves worked as well as the did. We have the appropriate control voltage dropping resistor assembly for when the time comes to hook it up to 600 VDC. This exercise was mostly to confirm our understanding of the schematics. Before tearing down the setup we recorded the clips that was used in this video. We have not disassembled the switch group or the individual switches but will do so before installing the system. The unit switch was likely overhauled before going into the warehouse in Everett so we are hopeful to find mostly good things inside.

Work on Narcissus continues. Several years ago we came to realize (accept) the condition of the sills required replacement. After a long search we found some period timbers that yielded two nice "new" sills. The 11 1/2 x 13 Heart pine beams had been removed from a brass foundry that was built in 1880. Our 5x8 sills wept sap from the knots after being milled 140 years after they were installed in the foundry. The upper structure was raised off the frame to facilitate sill replacement. Many window posts were replaced due to decay at the end grain cuts at the belt rail. We've fabricated many new door posts for the vestibules, new crowns, replaced "S" Beam ends and patched some of the other wood beams in the vestibule area. A lot of work goes unnoticed by those in the visitors gallery. We are hoping to be reinstalling the sills and steel channels, crown pieces, vestibule structures etc in time for summer visitors to notice the change. Then it will be on to wall and roof sheathing.

Parallel efforts were started to clean up and start the conversion of some trucks that will be used. Motors were selected and overhauled. This work on the control group was also being done during that time frame. As with any project of this scale donations also pace progress.

Thanks for your comments. I'll pass them on to Brian. I'm also interested in feedback on the video content. We expect to do an updated version when more of the components are cleaned up and operational and any feedback would be helpful.
Ernie Eaton

Read more about Narcissus at:
http://narcissus1912.blogspot.com/2023/02/narcissus-restoration-update-2-12-2023.html

Point of clarification... I was under the impression that the two letter code Westinghouse used was as follows:

First letter is the acceleration characteristic, H = Hand, A = Automatic.
Second letter is the control voltage, L = Line (high voltage), B = Battery (low voltage).

Am I misinformed?

You are correct. I should avoid making posts at 2AM! I had started typing something about whether this box was actually HB but then I deleted it. Let me edit the post to avoid future confusion!

Yeah, you have it. Ask Don Curry where it is. It is a very common booklet that WH published illustrating various types of HL control. A digitized copy may be on the HRA web site in the technical documents section. It looks like the circuit diagram that you cited in the video is actually from that handbook.

If you do not have the original electrical diagrams for the car you'll have some design work ahead to select the resistor values. The Richey book "Electric Railways" (another very common book which was reprinted by ARM) has some design info on this.

Some other letters I've encountered by reading these and other posts:
1st position
P Pneumatic
2nd position
C cam
K a kind of controller
3rd position
M modified

Examples:
PK = Pneumatically operated K controller
PCM = Pneumatic Cam Modified
but in Great Britain, which never had any original PC equipment, Brittish PCM is just called PC!

There are two types of controllers: platform and MU. With platform controllers, the motor currents and the change of resistance connections are contained inside the controller on the platform, right there in front of you; types:

R = straight resistance stepping, no reconnection of motors; one running speed: full.
K = series parallel, two running speeds: half speed and full speed.
B = a K controller equipped with braking positions.

MU controllers operate a set of contactors which carry the motor currents, removing them from the platform and confining them underneath the car floor or in an enclosed cabinet. WH and GE used slightly different terminology and symbol sets, both of which were semi-mnemonic. MU control system designations can become complex, particularly after about 1930.

Westinghouse: XY, where X=type of advance process (acceleration) and Y=control system operating voltage source.
X: H = Hand; A = Automatic
Y: B = Battery; L = line (trolley with dropping resistor)
These are followed (usually) by the master controller designation, which is and indication of control circuitry configuration.
Thus the Narcissus has/had WH HL 15-B controls, and LVT 1030 has HL 15-E12. Rapid transit control were usually "AB", automatic advance at battery voltage, particularly after about 1910.

GE: M = Magentically operated contactors, P = Pneumatically operated contactors, C = Cam operated contactors
With GE, these symbols are combined slightly differently, without reference to control voltage source and with the advance process specified in the title block of the connection diagram. For example, Key System bridge units use GE "non-automatic advance type M control" (with C-6-J controllers), which is readily abbreviated "GE M C-6-J". The SP Oakland, Alameda, & Berkeley cars used "automatic advance type M control" (with C-35 controllers), abbreviated "M C-35". The C&LE Red Devils use GE PC "pneumatic cam" (with C-129 controller). All three of these systems operate from line voltage. The SN 650 class electric locomotives use PCL (with C-168-A controllers), which means "Pneumatic Cam at Line voltage". All but two of the contactors are pneumatic, just like WH HL, and the "C" refers to the cam operated series-parallel switch.

These alphabet soups could become complex: the CTA 4000s use WH ABLFM, which stands for "Automatic advance at Battery or Line voltage, with Field control, compatible with (GE) type M". Just to keep things clear, the apparatus nameplates on 15 or 20 of the higher number of Key System bridge units read "Sprague-General Electric Type M Control System Manufactured by the Westinghouse Electric and Manufacturing Company".

Those controllers for the Narcissus are 15-Bs (from SF Muni iron monsters), and I've just discovered that there are at least two different circuitry configurations for them, depending on the model of switchgroup (essentially 264 type or 480 type).

Edit: took a look at the video, and you have the 264 type. The HL booklet referred to earlier is WEMCO Instruction Book No. 5143, which has a red cover. It was reprinted by ARM in the 1980s.

or "Magnetic"

These terms such as "AB" "HL" "PCM" mean very little in terms of maintenance, theory of operation, or spare parts. They were sales/marketing names. For example, any WH system which achieves automatic acceleration and battery trainlines could be AB, from the notching-head style, turret, 214 and 251 style groups (some of which had internal "PK" pneumatic mini-drum controllers, or sequence switches), up to the UP-style. Maybe they included dynamic braking too. All "AB"

As for GE's "PCM" there were two totally different things called PCM. One in the late 20s / early 30s which was, in fact, a pneumatic cam, and then in the 1940s, the "P" magically stands for "pilot motor" and the camshaft controller looks suspiciously like that from an all-electric PCC, but without the commutator-style rheostat. WH HL was almost always pneumatic unit switches, except for when they substituted an all-magnetic version (for example, the DifCo crane at Arden). As for GE "PCL" I always parse that as "pneumatic contactor locomotive" because the product was effectively a pneumatic version of type M locomotive control (unit switches, drum reverser)

I don't think a true technical inventory of brake and control equipment among preserved electric cars has ever been undertaken.

Thanks, I took a look and we have an electronic version of of 5134B which we have been referencing.